Assisted Migration (Assisted Colonization, Managed Relocation) and Rewilding of Plants and Animals in an Era of Rapid Climate Change


EDITOR'S NOTE: This annotated and linked list of online-accessible papers, articles, and news reports on assisted migration (aka: assisted colonization / colonisation, translocation, managed relocation) aims to further professional and popular understanding of both the substance and history of debate and actions regarding one of the most significant developments in conservation biology. This list is continually updated; entries are ordered only loosely by date, with more attention given to academic importance, insight into shifting conservation values, expansive treatment of the debate, and provision of background understanding.

  • FORESTERS OPEN TO ASSISTED MIGRATION: Most academic papers that have been cautious or critical of assisted migration as a management tool for coping with climate change have been written within the paradigm and professions of conservation biology and restoration biology. As you scroll down this list, most of the online entries are of that group. But forestry professionals are far more open to assisted migration — and have been engaging in it for a long time. Click to jump to the special section on "Assisted Migration for Forests of North America".

  • "Assisted migration" articles/papers (which primarily deal with helping extant species move as climate changes) are listed immediately below. Click to skip down to where "Pleistocene Rewilding and Taxon Substitution for Ecological Restoration" begins.


    IPCC 2014 Report

    Climate Change 2014

    Impacts, Adaptation, and Vulnerability"

       In the 44-page "SUMMARY FOR POLICYMAKERS" of this multi-volume report, Figure SPM.5, along with its caption and a summary paragraph, refer not only to the possible need for "assisted species migration", which ongoing climate change could necessitate to avert extinction and ecological disruptions, but also points to trees as being the most vulnerable of all life forms — and thus the most in need of human assistance to keep pace with climate zone changes. Trees are represented in the left-most vertical bar in image left, "Maximum speed at which species can move (km per decade)".

    (p. 15) "Many species will be unable to track suitable climates under mid- and high-range rates of climate change during the 21st century (medium confidence). Lower rates of change will pose fewer problems. Some species will adapt to new climates. Those that cannot adapt sufficiently fast will decrease in abundance or go extinct in part or all of their ranges. Management actions, such as maintenance of genetic diversity, assisted species migration and dispersal, manipulation of disturbance regimes (e.g., fires, floods), and reduction of other stressors, can reduce, but not eliminate, risks of impacts to terrestrial and freshwater ecosystems due to climate change, as well as increase the inherent capacity of ecosystems and their species to adapt to a changing climate (high confidence)."


  • "University of Arizona Study: Evolution Too Slow to Keep Up with Climate Change" press release of "Rates of projected climate change dramatically exceed past rates of climatic niche evolution among vertebrate species" by Ignacio Quintero and John J. Wiens, Ecological Letters August 2013 (abstract)
    EXCERPT (from press release): "Many vertebrate species would have to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years, a study led by a University of Arizona ecologist has found. . .  terrestrial vertebrate species appear to evolve too slowly to be able to adapt to the dramatically warmer climate expected by 2100. The researchers suggested that many species may face extinction if they are unable to move or acclimate. . . The sampling covered 17 families representing the major living groups of terrestrial vertebrates, including frogs, salamanders, lizards, snakes, crocodilians, birds and mammals.

  • "Plan Seeks 'Chaperones' for Threatened Species" news report on a talk by Adam Smith (ecologist at Missouri Botanical Garden) presented at the Ecological Society of America meeting, August 2013. Report by Virginia Gewin, published in Nature 09 August 2013
    EXCERPT: "Critics claim that such 'assisted migration' could transform struggling species into destructive invaders, or inadvertently transmit disease, or that hybridization between species could occur that would lower the planet's overall genetic diversity. But without some form of assistance, many plants will face certain extinction as the planet warms. With that in mind, researchers are proposing a heavily supervised form of assisted migration — using a network of more than 3,100 botanical gardens to 'chaperone' plant relocations. . . The researchers recommend that endangered species collected in the wild should be relocated to botanical gardens in stages, moving between gardens following a dispersal path that would be considered an evolutionarily realistic response to climate change. . .  With few other options for preserving rare and threatened species in the face of global warming, [Adam] Smith and his colleagues are forging ahead with their plans. They aim to release a more detailed proposal in October at the 5th Global Botanic Gardens Congress in Dunedin, New Zealand, that is likely to include a list of candidate species. They also hope to start a pilot project soon to test the feasibility and cost of chaperoning.

    See also the detailed blog on this topic by Kate Whittington, "Plant Pioneers: Assisting The Migration Of Climate-Endangered Species".

  • Assisted Migration Debate Takes a Sharp Turn in May 2013 - On May 8, CO2 in the atmosphere reached 400 ppm for the first time in human history. On May 9, Science journal published a stunning analysis of Siberian lake-sediment data that offers irrefutable evidence that a 400 ppm atmosphere (when it equilibrates air and ocean conditions) will produce an ice-free Arctic. Henceforth, responsible discourse about assisted migration will no longer question should it be undertaken, but rather when, how, and by whom. Below are the key links to the May 9 paper, beginning with the paper's title and abstract page.
  • "Pliocene Warmth, Polar Amplification, and Stepped Pleistocene Cooling Recorded in NE Arctic Russia" by Julie Brigham-Grette and 15 international coauthors, in Science May 9, 2013.

  • "The Arctic was once warmer, covered by trees": Pliocene epoch featured greenhouse gas levels similar to today's but with higher average temperatures", reported by Erin Wayman in Science News, 9 May 2013.

  • "Climate Sensitivity Stunner: Last Time CO2 Levels Hit 400 Parts Per Million The Arctic Was 14°F Warmer!", blogpost by Joe Romm, 12 May 2013

  • "Managed Relocation: Integrating the Scientific, Regulatory, and Ethical Challenges" by Mark W. Schwartz and 30 coauthors, BioScience August 2012 (12 pp in pdf)
    EXCERPT: "We report on the findings of the Managed Relocation Working Group (MRWG), an independent collection composed of over 30 scientists, scholars, and policymakers that met to discuss dimensions of managed relocation. Managed relocation raises a difficult suite of biological, legal, and ethical issues. Owing to the nature of this committee, most of the examples refer specifically to the United States, but the issues we treat are broadly applicable, including those related to policy. The MRWG represents an interdisciplinary group seeking a comprehensive consideration of managed relocation.
        "Conservation ecologists are beginning to call for adapting management strategies for climate change (e.g., increasing the connectivity, resistance, and resilience of natural protected areas; e.g., Heller and Zavaleta 2009). Others have suggested more radical approaches, such as embracing novel anthropogenic ecosystems as a management goal (Hobbs et al. 2006, Thomas 2011). The proponents of managed relocation contend that conventional conservation strategies will not provide sufficient protection from future environmental change (Vitt et al. 2010, Thomas 2011).
        "Our view is that the starting point for developing a decision framework for managed relocation should be an examination of the goals of conservation, values underlying those goals, and the possibility for conflict among both goals and underlying values. The next step is to examine the legal and institutional framework within which managed relocation decisions are made. Third, we must develop and agree on scientific standards of evidence to support managed relocation decisions. Finally, we must create tools for resolving goal or value conflicts. Toward this end, the MRWG identified a series of ethical, policy, ecological, and integrated questions that should be answered to support a socially and scientifically acceptable decision framework.
        "There are thorny ethical questions surrounding any shift to an adaptationist understanding of conservation ethics and policy that would sanction managed relocation. The conservation message for decades has stressed the importance of saving species within historical ranges. Managed relocation may create perverse opportunities for relaxing societal commitments to habitat protection (Camacho 2010). Perhaps an even more troubling question is whether the acceptance of adaptive and anticipatory strategies, such as managed relocation, will function as a moral hazard by undercutting society's resolve to pursue aggressive climate change mitigation policies. There is a danger that even a measured adoption of managed relocation will encourage ethically irresponsible behavior. Policies sanctioning managed relocation could therefore provide leverage to those who wish to dismantle legal and policy tools designed to protect species and their habitats. Policymakers will have to take great care in communicating the need for relocation proposals to a public with divided interests so that policy revisions do not confuse and weaken human ethical responsibilities toward conservation."
        Editor's note: This paper is an ideal place to learn about the full history of and key publications on this issue, as of mid 2012. The table below is reprinted from this paper.

  • COMMENTS (on the above 31-coauthor paper), along with RECOMMENDATIONS for further policy work, were posted by Connie Barlow, Torreya Guardian, December 2012.
  • "An Assessment of Invasion Risk from Assisted Migration" by Jillian M. Mueller and Jessica J. Hellmann, Conservation Biology, 28 June 2007.
    Content: Distinguishes history of inter- v. intra-continental invasive species in assessing the risks. Concludes that fish and crustaceans may pose a high risk. "We conclude that the risk of AM to create novel invasive species is small, but assisted species that do become invasive could have large effects."

  • "Translocation of Species, Climate Change, and the End of Trying to Recreate Past Ecological Communities" by Chris D. Thomas, Trends in Ecology and Evolution, May 2011.
    Abstract: Many of the species at greatest risk of extinction from anthropogenic climate change are narrow endemics that face insurmountable dispersal barriers. In this review, I argue that the only viable option to maintain populations of these species in the wild is to translocate them to other locations where the climate is suitable. Risks of extinction to native species in destination areas are small, provided that translocations take place within the same broad geographic region and that the destinations lack local endemics. Biological communities in these areas are in the process of receiving many hundreds of other immigrant species as a result of climate change; ensuring that some of the 'new' inhabitants are climate-endangered species could reduce the net rate of extinction.

    EDITOR'S NOTE: For suggested standards for translocations of aquatic species, see "Challenges and Opportunities in Implementing Managed Relocation for Conservation of Freshwater Species" by Julian D. Olden et al., Conservation Biology, February 2011. See also "Standards for Assisted Migration, which was posted on the Torreya Guardians website in 2004.

  • "The precautionary principle in managed relocation is misguided advice" by Mark W. Schwartz, Jessica J. Hellmann, and Jason S. McLachlan, Trends in Ecology and Evolution 2009
    EXCERPT: "The precautionary principle has been historically useful in guiding conservation management, but global environmental change presents a different sort of problem. There are real risks of harm to biodiversity through inaction as well as action. The only way forward to confront unprecedented problems such as global anthropogenic climate change is careful risk analysis, including an honest evaluation of uncertainty and potential harm, along with broad public debate beyond the technical expertise of scientists and managers. We must engage in careful study of ethical, legal and biological issues surrounding the idea of managed relocation even if the ultimate conclusion is that it is the wrong approach to managing a difficult problem."
    NOTE: The September 2009 issue of Trends in Ecology and Evolution contains a total of 6 short papers or opinion pieces on the issue of assisted migration.

  • "Commercial trade of federally listed threatened and endangered plants in the United States" (abstract) by Patrick D. Shirey et al., Conservation Letters Sept/Oct 2013, pp. 300-316.
    Note: This paper clearly establishes the legality of non-commercial translocations ("assisted migration", "assisted colonization") of endangered plant species in the USA. The voluntary efforts of citizen-naturalists in Torreya Guardians (assisting the northward movement of Torreya taxifolia) are used as a key example of such legal practices.

    EXCERPTS: "a listed plant could be purchased in one state and then transported to another state without violating the ESA, so long as the plant was taken from and planted on property not under Federal jurisdiction, such as private property. Furthermore, the ESA does not prohibit an individual from giving listed plants as a gift to someone in another state so long as a change in plant ownership is not in the pursuit of gain or profit." . . . In the United States, the structure of the Endangered Species Act, coupled with inadequate funding for endangered plant conservation, has encouraged citizens to undertake plant conservation, especially for charismatic plants threatened by climate change. For example, the Torreya Guardians have obtained plants and seeds of Florida torreya (Torreya taxifolia), and moved seedlings and saplings to the southern Appalachian Mountains, outside of the species' historic range (McLachlan et al. 2007; www.torreyaguardians.org). . . In contrast to accepted ex situ conservation practices (Haskins & Keel 2012), the Torreya Guardians established private experimental populations on the property of cooperative landowners to help preserve the species outside of its historic range because of its decline, lack of federal funding, and the availability of privately owned and commercially available plants and seeds. . . Finally, under U.S. federal law, citizens who move a listed plant are not constrained by the same assessment process as the federal government — their actions are legal under the ESA without a review of their plans. MORE EXCERPTS available in PDF. See also "Scientific American blog" on this topic (July 2013).

    Note: Because the Shirey et al. paper established the legality of Torreya Guardian actions "rewilding" an endangered conifer tree (Torreya taxifolia) far north of its climate-stressed "critical habitat," activist Connie Barlow recorded in November 2013 a 75-minute VIDEO BLOG (right), posted on Youtube, to summarize the group's learnings to date.

    Note: To go directly in the video to the importance of the Shirey et al. paper, click here, or click on the "Show more" link below the Youtube caption and see the full table of contents of the video, hotlinked by time codes.

      

  • "The Nature Conservancy: Adaptation Forestry in Minnesota's Northwoods" July 2013 status report by The Nature Conservancy.
    EXCERPTS: "In June 2013, over 33,000 seedlings from a combination of species and seed zones were planted at several project sites in northeastern Minnesota. Further planting will occur in 2014.

    "The Nature Conservancy is coordinating this project, in collaboration with the Northern Institute of Applied Climate Science (NIACS), University of Minnesota-Duluth, and other organizations. The project is being implemented on approximately 2,000 acres of forestland in northeastern Minnesota, on a mix of federal, state, and county land.

    "Much of current forest management in northeastern Minnesota focuses on maintaing and restoring native boreal species, such as aspen and white spruce. At the same time, forest composition in northeastern Minnesota is projected to change as the climate changes, and recent research suggests that these same species are at greater risk in a changed climate. These anticipated changes suggest that, in the long term, climate change may be working in direct opposition to some current restoration management actions.

    Modeling studies project changes in forest composition in northeastern Minnesota under future climate scenarios, including a shift towards more maple and a less diverse forest composition across the northern forested landscape. This suggests that many of the tree species that are currently a focus of restoration efforts, with the exception of white pine, may be unsuited to future conditions compared to more southerly distributed species, such as maples and oaks. More details are available in the TNC Background Study Summary."

    Note: See a superb, long popular article on this assisted migration action in a 2013 issue of the Minneapolis Star Tribune: "Saving the Great North Woods". Excerpt: "Driven by a warming climate, scientists predict, the [boreal forest in NE Minnesota] will soon follow the glaciers and retreat north by as much as 300 miles in the next century. Much of northern Minnesota, they say, will become open savannas like those in Nebraska and eastern Kansas — with grasses and brush, a few scattered trees, and domes of bare rock rising from the ground.

  • "Species Conservation, Rapid Environmental Change, and Ecological Ethics" by Ben A. Minteer, The Nature Education Knowledge Project 2012
    EXCERPT: "Rapid, large-scale environmental changes are forcing conservationists to consider innovative and often controversial tactics for protecting species in this century, tactics that raise significant ethical and value-laden questions. Given what we already know about changes in species' ranges and abundances in the face of global climate change, it is inevitable that conservation in the post-preservationist era will require more interventionist conservation policies, leading to debates regarding risks, benefits, and likely success of novel practices such as managed relocation."

    See also Minteer's "Restoring the Narrative of American Environmentalism", January 2013, Restoration Ecology.


    VIDEO ABOVE LEFT: Alejandro Camacho 2011: Redefining Nature through Assisted Migration (Natural Resources Law and Ethics Under Climate Change; 21 minutes)

    29:19 Begins • 31:21 Torreya example • 32:42 "Why do it, and why is this controversial? The existing literature focuses on whether assisted migration can be done — what I call, questions of scientific viability or legality. But I argue that the concerns with it, at their root, are deeply normative. They're really ethical. Assisted migration challenges deeply entrenched ideas about what the purposes are of natural resource law and natural resources management. But I argue that it is these principles and the legal framework that require rethinking." • 40:11 "We need to reinvent resource management to better reflect a dynamic world … "Natural resources management was not designed with climate change in mind." • 47:35 "I argue that climate change necessitates managing for the future." • 51:19 "I think assisted migration illustrates how resource management is not exclusively a scientific or legal inquiry."

    VIDEO ABOVE RIGHT: Alejandro Camacho 2012: Why Federal Climate Change Legislation Shouldn't Stop States from Innovating in Adaptation Efforts (29 minutes)

    00:01 Begins • 01:24 "My claim is that the law in the United States is not well suited to cultivate successful adaptation because it's not designed to foster learning." • 02:12 "U.S. law is not well suited to foster adaptation because it relies on (in fact, promotes) a very static view of nature and natural systems." • 04:45 "Climate change adaptation in particular is problematic because determining what are suitable adaptations is largely affected by the extent of mitigation … And we don't know that … So knowing what adaptation strategies to adopt, to restore certain mangroves, when we don't actually know if 50 to 100 years from now, whether all that work is wasted, is really problematic." • 06:21 "Scientists are really being challenged to reconsider long-held assumptions and long-held methodologies they've relied on. Regulators and managers are being asked to prepare for problems that they haven't ever faced before." • 06:54 "The most important strategies for effective adaptation, therefore, are those that help reduce uncertainty and that promote learning by managers and stakeholders in particular. [He cites 2 problems in the US] (1) Agencies are really slow to adapt to new information or changed circumstances. They aren't required to adjust their strategies over time … They don't gather information as to the effectiveness of their strategies; so the consequences are weak accountability. (2) Natural resources management in the U.S. is very fragmented, with at best weak coordination. It's not designed with climate change in mind. … It also hinders the capacity for learning between agencies." • 11:18 "Natural resources law in the United States is badly fitted for addressing the effects of climate change because of its goal, because of its objectives … grounded in a preservationist or restorationist baseline, a historical baseline . . . shielding nature from active human intervention … minimizing non-native and protecting native … Climate change reveals the limits of both of these versions of preservationism." • 15:23 "There is little ethical foundation for arresting the evolution of pre-existing ecosystems … Some of the reserves that have been set aside may actually become inhospitable to the very resources that they were created to protect." • 16:08 "Finally, climate change really pits these two different types of preservation — wildness preservation and historical preservation — against each other. Climate change makes it impossible to do both. You can't keep things the way they are and also leave them alone." • 22:02 "By not requiring agencies to monitor, to revisit, to adjust their decisions, to learn, this makes agencies less accountable to the public." • 25:15 "What climate change makes clear is that ecology and natural resource management should not be left solely to an expert: an economist, an ecologist. These are democratic decisions." • 29:00 Q&A starts

    See also print versions of these papers:

    2011: Alejandro Camacho's 2011, "A Learning Collaboratory: Improving Federal Climate Change Adaptation Planning"

    2010: "Why Federal Climate Change Legislation Shouldn't Stop States From Innovating in Adaptation Efforts"

    Note: Serious students of assisted migration or, more broadly, the need for profound professional and public reconsideration of ecological norms in a time of rapid climate change will find it important to read the 86-page (freely downloadable) paper by Camacho, quotations from which follow:

  • "Assisted Migration: Redefining Nature and Natural Resource Law Under Climate Change", by Alejandro E. Camacho, 2010, in Yale Journal on Regulation, vol 27, pp 171-255.
    [86-pages in PDF freely downloadable] Argues for the necessity of assisted migration, owing to ongoing and projected climate change, and suggests changes in the U.S. ESA and regulatory policies for making this possible. Boldly addresses ethical concerns and the need for public discussion in the context of how assisted migration is a leading-edge issue that reveals the scope to which ecological preservation, restoration, and management will need to be thoroughly in light of the new awareness of significant climate change. Key quotations:

    Page 189: "Paradoxically, as detailed in the following subsections, under existing law it may often be more difficult for federal agencies to engage in assisted migration than it is for private parties."

    Page 243: "Assisted migration illustrates how climate change compels a reassessment of three key features of modern American natural resource governance. First, assisted migration demonstrates how climate change inevitably compels a reassessment away from baseline goals that seek to preserve or restore historical or existing conditions to a focus on maximizing desirable future conditions, although the particular formulation of such a goal for natural resource management is very much unresolved. Second, while making clear that biotic interactions will change considerably with or without direct human involvement, climate change necessarily reshapes the primary unit to target for management away from individual species or even assemblages of species toward ecological processes. Yet again, concretely steering resource management toward such a focus remains elusive. Third, the swiftness of climate change demonstrates that distinctions previously made in natural resource policy between native and exotic, or between natural and introduced, are overly simplistic and anchored in the flawed notion that the world is inert. Public resource management must explore new management standards for determining what ecological conditions are desirable or acceptable. Each of these necessitates substantial further public discussions to ascertain the future of public natural resource policy — and thus the prospects for assisted migration."

    page 244: "The conflict over assisted migration shows that the goal of preserving or restoring resources to a historic baseline that currently dominates natural resource policy will be increasingly difficult if not impossible to sustain. More than ever, modern anthropogenic climate change emphasizes the necessity of actively managing for the future. Yet the particular shape of such an objective is far from clear. As such, climate change necessitates extensive public discussions and ultimately legislative guidance regarding what is valuable and important to the public about natural resources such as endangered species and existing biotic communities."

    page 245: "Similarly, natural resource management must be transformed away from a primary focus on preserving or restoring historical biotic assemblages. With significant alterations in climatic conditions anticipated for many ecosystems, preservation and restoration goals will be increasingly unsustainable. Accordingly, statutes like the National Park Service Organic Act and Wilderness Act that primarily seek to preserve historical conditions will need to be reconceived away from a strict fidelity to the past toward a greater focus on promoting desirable future conditions in light of climatic changes."

    Page 251: "Lastly, assisted migration demonstrates the flaw in relying on absolute dichotomies such as native/exotic and natural/artificial as core features of managing biological systems under global climate change. Though such complete dualism has the advantage of simplicity, it is neither accurate nor helpful in deliberations over how to manage and choose among resources as ecological systems change with climatic conditions. Dedicating substantial resources to preserving and restoring a particular biological unit because it existed at one point in time in an ecosystem makes little sense if climatic conditions make the landscape inhospitable to that unit. Similarly, what is the ethical or scientific justification for prohibiting or removing any organism simply because it never existed in a particular location, especially if that organism is now well‚Äźmatched with the location due to changes in climatic conditions?"

    Page 253: "Though this Article provides a preliminary framework for assessing both when to allow and how to manage experimentation with assisted migration, it more importantly explains how climate change reveals a host of value questions that remain unexplored in natural resource law and policy. The resolution of these questions will shape not only determinations regarding the acceptability of assisted migration, but more broadly the future of natural resource management."

    Page 255: "In summary, a regulatory framework that fosters open and transparent access, debate, and deliberation can promote agency accountability to democratic representatives and the general public, and more informed public deliberation and action with regard to the management tradeoffs that must be made in devising goals and sandards for natural resource management. Though developing such institutions and processes will be far from easy, such a pursuit unquestionably should be the focus of natural resource law in a world of rapid climate change. The prior account of a pristine and untouched nature may be nearing its end. However, the opportunity to help foster biotic and human communities that truly integrate humanity's collective self-interest in resource conservation and duties of stewardship has really just begun."

    SEE ALSO: "Assisted Migration: A Viable Conservation Srategry to Preserve the Biodiversity of Threatened Island Nations?", by Jessica Wentz, 2011, Columbia Law School Working Paper.


  • "Using assisted colonisation to conserve biodiversity and restore ecosystem function under climate change" by Ian D. Lunt et al, Biological Conservation, Vol 157, 2013
    EXCERPT: "To date, the assisted colonisation literature has focused primarily on a single rationale: to enhance the survival prospects of the taxon being moved, or small numbers of interdependent taxa, such as butterflies and host plants (Hellmann, 2002). However, here we suggest that assisted colonisation could also be undertaken to achieve a very different conservation goal — to maintain declining ecosystem processes. Adopting the terminology of Seddon (2010), this type of assisted colonisation would be classified as ecological replacement — the release of "a species outside its historic range in order to fill an ecological niche left vacant by the extirpation of a native species", and is akin to the "anticipatory restoration" activities proposed by Manning et al. (2009). This goal may become prominent in future climate change adaptation programs as the impacts of climate change become more severe, but the juxtaposition of goals has not been considered in the assisted colonisation literature and demands benefit-risk evaluation.
        "For simplicity, we characterize these two contrasting rationales for assisted colonisation as 'push' and 'pull' strategies. Push strategies that focus on conserving individual taxa or small groups of inter-dependent taxa are already widely discussed in the assisted colonisation literature. In these cases, issues such as rarity and threat guide the selection of target taxa, and populations are 'pushed' into one or more localities where it is expected that they will maintain viable populations for an extended period under climate change (e.g. Willis et al., 2009). Risk assessments are required to ensure that informed decisions are made to relocate taxa such that there is minimal impact on other species where they are introduced (Burbidge et al., 2011). In contrast, assisted colonisation that is also motivated by a desire to restore ecosystem function should expect to have an appreciable impact at the recipient site. In such 'pull' scenarios, desired ecosystem functions and potential recipient sites would first be identified, and appropriate candidate species would then be 'pulled' into recipient sites to maintain or restore the specified function. Relocation of taxa may be undertaken to deliver ecological functions that are directly affected by climate change, or where climate change exacerbates other causes of decline."

  • "Projected Climate-Driven Faunal Movement Routes" by J. J. Lawler et al., Ecology Letters 2013
    ABSTRACT: Historically, many species moved great distances as climates changed. However, modern movements will be limited by the patterns of human-dominated landscapes. Here, we use a combination of projected climate-driven shifts in the distributions of 2903 vertebrate species, estimated current human impacts on the landscape, and movement models, to determine through which areas in the western hemisphere species will likely need to move to track suitable climates. Our results reveal areas with projected high densities of climate-driven movements — including, the Amazon Basin, the southeastern United States and southeastern Brazil. Some of these regions, such as southern Bolivia and northern Paraguay, contain relatively intact landscapes, whereas others such as the southeastern United States and Brazil are heavily impacted by human activities. Thus, these results highlight both critical areas for protecting lands that will foster movement, and barriers where human land-use activities will likely impede climate-driven shifts in species distributions.
         EDITOR'S NOTE: The 2,903 vertebrate species modeled do not include any species for which bioclimatic projections indicate that discontinuities in livable landscapes will block easy species movements to respond to climate change. Hence, those vertebrate species that may require human-assisted migration were excluded from the study results.
         EXCERPTS: "The southern Appalachian Mountains in the southeastern United States and the Atlantic Forest in Brazil were two prominent areas highlighted by our models as likely to have high concentrations of species movements. Both of these areas are suspected to have served as climate refugia in the past." . . . "Our models do not account for dispersal distances and thus some of the movements included in our results may be unrealistic as they may be in areas that a given species will not be able to reach in a 100-year period. Many moles, shrews and primates, for example, may not be able to disperse fast enough to keep pace with climate change in the Western Hemisphere (Schloss et al. 2012)."

  • 2014 Videoblog Series proposes assisted migration of common trees northward by Connie Barlow, founder of Torreya Guardians
        Barlow writes, "On January 4, I posted a new 42-minute videoblog on youtube that extends our learnings and experience within Torreya Guardians to potentially apply to private landowners throughout the USA who want to begin experimenting on their own lands with helping even common tree species (especially large-seeded species dependent on squirrels for range extension) to move northward in anticipation of climate change — climate change that may push habitable ranges northward faster than the trees can "move" on their own. I offer a name for that new citizen forestry initiative: Leaf a Legacy."

    Access video: "Climate, Trees, and Legacy".

  • "Restoration Ecology" blogpost by Julissa Roncal, 7 July 2012
    EXCERPT: As a plant ecologist at Fairchild Tropical Botanic Garden I was part of a team led by Dr. Joyce Maschinski working on the conservation and restoration of endangered species in South Florida. We addressed questions like: Can endangered species be translocated outside their historic distribution range? Have the fundamental and realized niches changed due to anthropogenic influence? Does the new suitable habitat support favorable biotic interactions? What should be the genetic source to establish new populations? Do seeds, seedlings, cuttings, or adults are better transplant material? We conducted experimental introductions of several endangered species to answer these questions, and to reduce extinction risk, learn more about the biology of rare species, and advance restoration ecology theory. Our experimental results indicated that the species Amorpha herbacea (Fabaceae) can be translocated outside its known historic range, however, highest growth was attained on a different microhabitat than was historically known, reflecting the influence of anthropogenic disturbance on native plants’ future optimal habitat.

  • "Testing alternative models of climate-mediated extirpations?"(American Pika) by Erik A. Beever et. al, Ecological Applications January 2010
    EXCERPT: "Research on American pikas (Ochotona princeps) in montane areas of the Great Basin during 1994-1999 suggested that 20th-century population extirpations were predicted by a combination of biogeographic, anthropogenic, and especially climatic factors. Surveys during 2005-2007 documented additional extirpations and within-site shifts of pika distributions at remaining sites."
        Editor's Note: See also the 2012, "Not-so-splendid isolation: modeling climate-mediated range collapse of a montane mammal Ochotona princeps [American pica] across numerous ecoregions", which includes "Nineteen of the 31 traditional US pika subspecies were predicted to lose > 98% of their suitable habitat under a 7 degree C increase in the mean temperature of the warmest quarter of the year, and lineages were predicted to lose 88 95% of suitable habitat. Under a 4 degree C increase, traditional subspecies averaged a predicted 73% (range = 44-99%) reduction." SEE ALSO 2012 book chapter by Chris Ray et. al, "Retreat of the Amerian Pika: Up the Mountain or into the Void?", which includes: "The majority of evidence for effects of climate on O. princeps derives from studies within the Great Basin . . . In this region, the species has been losing ground for at least 10,000 years: the minimum elevation of the pika's distribution has retracted upslope by nearly 800 meters once the last glacial maximum, eliminating some populations and isolating others."

  • "Can Vulnerable Species Outrun Climate Change?" by Emma Marris, Environment 360 3 November 2011
    EXCERPT: "Reagan Early says that before she completed her research [on the California Newt], she believed that physically moving species to help them reach suitable habitat — a strategy called 'managed relocation' or 'assisted migration' — was a bad idea. But the maps she made [of regional speeds of climate change during the past glacial], with those yawning gaps between the amphibians and the places where they could live happily in the future, changed her mind."

  • "How Fast Can Trees Migrate?" by Jacquelyn Gill, (blogpost) 8 May 2013
    Excellent overview with online links to the recent history, challenges, opportunities, and current issues on this question — especially drawing from the paleoecological literature focusing on pollen data.

  • "Forests Not Keeping Pace with Climate Change" by Zhu, Woodall, and Clark, Global Change Biology, November 2011
    EXCERPT of press release: The study found no consistent evidence that population spread is greatest in areas where climate has changed the most; nor do the species' response patterns appear to be related to seed size or dispersal characteristics. "Warm zones have shifted northward by up to 100 kilometers in some parts of the eastern United States, but our results do not inspire confidence that tree populations are tracking those changes," says Clark, who also holds appointments at Duke as a professor of biology and statistics. "This increases the risk of serious lags in tree migrations."

  • "Assisted migration could help plants find a new home" by Laura Nielsen (for Frontier Scientists blog in) Anchorage Daily News, 28 August 2013
    Excellent short overview of the current discussion on assisted migration, with some examples from northern plant biomes.

  • "Past and ongoing shifts in Joshua tree distribution support future modeled range contraction" by Kenneth L. Cole et al., Ecological Applications, 2011.
    EXCERPT: The future distribution of the Joshua tree (Yucca brevifolia) is projected by combining a geostatistical analysis of 20th-century climates over its current range, future modeled climates, and paleoecological data showing its response to a past similar climate change. As climate rapidly warmed 11,700 years ago, the range of Joshua tree contracted, leaving only the populations near what had been its northernmost limit. Its ability to spread northward into new suitable habitats after this time may have been inhibited by the somewhat earlier extinction of megafaunal dispersers, especially the Shasta ground sloth. All of the models project the future elimination of Joshua tree throughout most of the southern portions of its current range. Although estimates of future monthly precipitation differ between the models, these changes are outweighed by large increases in temperature common to all the models. Only a few populations within the current range are predicted to be sustainable. Several models project significant potential future expansion into new areas beyond the current range, but the species' historical and current rates of dispersal would seem to prevent natural expansion into these new areas. Several areas are predicted to be potential sites for relocation/ assisted migration.
         The Joshua tree example used here does have an added complication in that its migrational capacity to respond to changing climates seems to be extremely limited. There are no historical records of Joshua tree invasions into new habitat and even few documented instances of recent seedling establishment. Although the rapidly warming climate of the early Holocene (Steffensen et al. 2008, Cole 2010) would seem to have opened up vast new areas of potential range to the north, the fossil record does not record any significant northward expansion over the last 11,700 years. These facts coalesce with morphological observations of the plant's indehiscent fruits and the abundance of fruits and seeds in fossil ground sloth dung to support the concept that the species' current mobility is constrained by the earlier extinction of the Shasta ground sloth and other possible seed vector(s) (Janzen and Martin 1982, Lenz 2001).
         Although it is likely that some of these un-sampled areas with high levels of future climate potential, such as Nellis Air Force Base, are already occupied by Joshua tree, they could serve an important conservation function in the future. But other areas further from the current range in central Nevada, northwestern Arizona, and southwestern Utah could hold high potential for future relocation efforts, should such activities prove desirable and possible. Managed relocation, also known as assisted migration or assisted colonization, has become a controversial topic for conservation (Hoegh-Guldberg et al. 2008). Fortunately for Joshua tree, a majority of the areas predicted to be sustainable, within migrational range, or potential assisted migration sites, are already on federal lands or other protected areas.

    See also USGS press release: "Uncertain Future for Joshua Trees Projected with Climate Change".

    A superb 2013 photo-essay including staff interviews at Joshua Tree National Park is "Preventing a Joshua Treeless National Park".

  • "Reframing the Debate Over Assisted Colonization" by Joshua J. Lawler and Julian D. Olen, Frontiers in Ecology 24 March 2011
    EXCERPT: "In light of the difficulty in weighing the consequences of action versus inaction [re assisted colonization], we conclude that focusing the debate on this issue is counterproductive. In fact, we would argue that, given the magnitude of change that is likely to occur in many receiving ecosystems, there is little use in worrying about the effects of introducing one particular species. This is not to say that we should aban- don efforts to assess potential impacts to the receiving ecosystems. However, it does suggest that we consider the amount of change forecast for that ecosystem before conducting detailed experiments on a system that may not exist in the future."

  • "Hope in the Age of Man" by Emma Marris, Peter Kareiva, Joseph Mascaro, and Erle C. Ellis, New York Times 7 December 2011
    EXCERPT: "We can accept the reality of humanity's reshaping of the environment without giving up in despair. We can, and we should, consider actively moving species at risk of extinction from climate change. We can design ecosystems to maintain wildlife, filter water and sequester carbon. We can restore once magnificent ecosystems like Yellowstone and the Gulf of Mexico to new glories — but glories that still contain a heavy hand of man. We can fight sprawl and mindless development even as we cherish the exuberant nature that can increasingly be found in our own cities, from native gardens to green roofs. And we can do this even as we continue to fight for international agreements on limiting the greenhouses gases that are warming the planet. The Anthropocene does not represent the failure of environmentalism. It is the stage on which a new, more positive and forward-looking environmentalism can be built. This is the Earth we have created, and we have a duty, as a species, to protect it and manage it with love and intelligence. It is not ruined. It is beautiful still, and can be even more beautiful, if we work together and care for it."<

    EDITOR'S NOTE: For an opposing viewpoint, see "Conservation in the Anthropocene" by Tim Caro et al., Conservation Biology 2011.


          
  • VIDEO: Native Peoples Consider Assisted Migration of Plants (2012)

    Beginning at 10:18 into this United Nations video (featuring indigenous awareness of climate change around the world), mention is made of how native peoples in the USA are already looking a hundred or more miles south in order "to see what plants are similar to the plants that are thriving today, because those plants may no longer thrive on their reservation tomorrow. They are looking to see what relatives they may be able to move, to assist, from other places."


  • "8 Wild Proposals to Relocate Endangered Species" by Brandon Keim, Wired Science 1 February 2012
    The 8 proposals are for "assisted migration" and/or "rewilding" of: (1) Komodo Dragons and elephants to Australia (the former to predate on alien herbivores; the latter to graze down the fire-prone overgrowth of alien grasses). (2) Rewilding America's Great Plains with proxy herbivores and carnivores from Africa that are close kin of America's own beasts that went extinct at the end of the Pleistocene. A specific example would be (3) Bring Back the Cheetah to America's plains, where a larger cheetah (that went extinct 13,000 years ago) had co-evolved with America's unique pronghorn — the fastest hoofed mammal on Earth. (4) Saving Torreya taxifolia conifer trees, which are too sickly to reproduce in their historic range in northern Florida, by planting seedlings in the mountains of North Carolina (an action already undertaken and apparently succeeding). (5) Antarctic Polar Bears? is the least serious of any proposal, as it would have dire consequences for land-breeding penguins. (6) Whitebark Pine in the western USA, dying in part owing to rapid climate change. (7) Madagascan lemurs to a Caribbean island, to be financed by billiionaire Richard Branson. (8) Aldabran Tortoises to islands in the Indian Ocean a project advocated in 1874 by Charles Darwin and continuing with fresh impetus today — especially to islands in which closely related giant tortoises were hunted to extinction by humans.

  • "Britain Should Welcome Climate Refugee Species" by Chris Thomas, New Scientist 2 November 2011
    Popular adaptation of "Translocation of species, climate change, and the end of trying to recreate past ecological communities", an opinion piece in Trends in Ecology and Evolution, 15 March 2011. EXCERPT: "Britain is already home to around 2000 introduced species which have increased biodiversity while causing few, if any, major problems. True, there have been ecological changes, and we spend a lot of money trying to get rid of aliens, but Britain appears virtually immune to extinctions from introduced species. It therefore represents an ideal destination for endangered species from elsewhere in Europe. One is the Iberian lynx, the most endangered cat in the world. Establishing it in Britain would represent a great contribution to global conservation. Another is the Spanish imperial eagle; a third possibility is the Pyrenean desman, a semi-aquatic mammal restricted to streams in north-west Iberia. Various butterflies and water beetles might also find a suitable home in Britain. In fact, the vast majority of species endangered by climate change are likely to be plants and insects that would be relatively easy to accommodate. . . Conservation is now about managing change. Retaining or restoring the past is no longer feasible. We should avoid the unproductive question 'how can we keep things as they are?' and instead ask 'how can we maximise our contributions to global conservation?' One way will be to open our doors to endangered aliens."
        NOTE: See also, "Experts strive to re-introduce Norfolk's lost species" (reintroduction from Sweden of the pool frog that went extinct in the UK in 1993).

  • "Tending to Our Rambunctious Garden" Q&A with journalist Emma Marris, OnEarth 28 September 2011
    Emma Marris's 2011 book, Rambunctious Garden, has "Assisted Migration" as the topic and title for chapter 5. The Q&A linked above is an excellent short introduction to the reach of this book in highlighting the shifting norms and values in conservation biology and land management today. Assisted migration advocate Connie Barlow posted a positive review of the book on Amazon: "Rewilding, Assisted Migration, Ecological Restoration, and More". There's also an excellent dot-Earth video interview of Marris on youtube.

  • "The Age of Man Is Not a Disaster" - Op-ed by Emma Marris, Peter Kareiva, Erle C Ellis, New York Times 7 December 2011
    EXCERPT: "We can accept the reality of humanity's reshaping of the environment without giving up in despair. We can, and we should, consider actively moving species at risk of extinction from climate change."

  • "Regulate Trade in Rare Plants" by Patrick D. Shirey and Gary A. Lamberti, Nature 27 January 2011
    A groundbreaking "Comment" paper in one of the top science journals combines data analysis of 753 threatened or endangered PLANTS in the USA with policy and legal analysis of the as-yet largely unregulated trade in seeds and seedlings cultivated in private gardens and nurseries outside of the official native habitat. A very readable and thought-provoking exposition of pros and cons of business as usual, now that climate change is motivating conservationists (individually and in groups outside of government) to consider whether the imperiled plant species that they love might benefit from, or even require, their assistance ("assisted migration") — given that governmentally agencies are still hesitant to (and in some cases, prohibited from) expanding locations for conservation programs beyond so-called native range. The work of Torreya Guardians is highlighted, including a 2010 revision in the official ESA management plan for Torreya taxifolia, directing plan managers to attempt to coordinate activities with Torreya Guardians, where possible. The authors conclude: "Although the redistribution of plant species around the world is nothing new, the ease with which people can now obtain and transfer specimens is unprecedented. This, combined with a growing interest in assisted colonization, makes it more important than ever for federal and local governments to wrest control of illegal Internet trade, develop a policy for hybrids and ensure that genetic diversity is considered when propagating plants. 3 pages in PDF for purchase online.

    News articles on this paper: in Science Daily; Los Angeles Times.

    Note: In 2013 the Shirey et al. published a much more complete report on the same topic: "Commercial trade of federally listed threatened and endangered plants in the United States" (published in the Sept/Oct issue of Conservation Letters.

    Note: The authors, Shirey and Lamberti, published another primary resource on the issue of assisted migration in 2010. Scroll below to the title "Assisted Colonization Under the U.S. Endangered Species Act."

  • "Move it or lose it? The ecological ethics of relocating species under climate change" by Ben Minteer and James Collins, Ecological Applications October 2010
    Lead author Ben Minteer is an environmental ethicist, and this paper is a strong and compelling piece of well-supported advocacy in favor of "managed relocation" (aka "assisted migration). The final paragraph reads: "If we value wild species and wish to bequeath a significant fraction of global biodiversity to future generations, radical strategies like managed relocation may well be our last best chance. Although risky, such bold efforts to preemptively move threatened species to new environments may offer the only hope to keep them from moving into museums and zoos—and haunting our ecological conscience." 4 pages in PDF.

  • "Future Human Intervention in Ecosystems and the Critical Role for Evolutionary Biology" by Jessica J. Hellmann and M.E. Pfrender, Conservation Biology December 2011
    EXCERPT: "We expect that considerable philosophical and conceptual change will occur within conservation biology over the next 25 years. If we acknowledge that the human population is growing and that the rapid pace of global change, including climate change, will continue, then we need to begin managing systems that are constantly changing—we can no longer look to the past for guidance on how an ecosystem is supposed to be."

  • "Guardian Angels" article by Janet Marinelli, Audubon Magazine, May/June 2010.
    In-depth exploration of "the biggest controversy in contemporary conservation science." Engagingly written for both a popular and professional audience, journalist Marinelli draws from her interviews with leading scientists, horticulturalists, and activists to present the core arguments for and against assisted migration. A site visit to an endangered plant breeding facility (the Atlanta Botanical Garden) is paired in the article with Marinelli's eye-witness description of "eco-vigilante" action, when the loose-knit citizens group Torreya Guardians intentionally planted into forested landscapes of mountainous North Carolina 31 seedlings of the highly endangered Florida Torreya — an assisted migration of some 400 miles northward of historically known native habitat.

  • "Paleoecology and the Assisted Migration Debate: Why a Deep-Time Perspective Is Vital" online essay by Torreya Guardian Connie Barlow, February 2011.
    Connie Barlow (with assistance from Russell Regnery) has posted a short, 11-point summary essay that aggregates the data and develops strong scientific reasoning in favor of assisted migration for Torreya taxifolia. The essay also advocates a shift in the foundational paradigm from assuming 1491 is the proper time-standard for assessing native range to a "deep-time" perspective grounded in a paleoecological understanding that native ranges for all plants in temperate latitudes of the Northern Hemisphere have undergone substantial altitudinal and/or latitudinal migrations that have tracked changes in climate during the past several million years of Pleistocene glacial and interglacial cycles.

  • "Climate Change and Forests of the Future: Managing in the Face of Uncertainty,", by Constance I. Millar et al., Ecological Adaptations, 2007.
    EXCERPT: Establish 'neo-native' forests. Information from historical species ranges and responses to climate change can provide unique insight about species responses, ecological tolerances, and potential new habitats. Areas that supported species in the past under similar conditions to those projected for the future might be considered sites for 'neo-native' stands of the species. These may even be outside the current species range, in locations where the species would otherwise be considered exotic. For instance, Monterey pine (Pinus radiata), endangered throughout its small native range, has naturalized along the north coast of California distant from its present native distribution. Much of this area was paleohistorical range for the pine, extant during climate conditions that have been interpreted to be similar to expected futures in California. Using these locations for 'neo-native' conservation stands, rather than removing trees as undesired invasives, is an example of how management could accommodate climate change. (p. 2148)

  • "Taking Wildness in Hand: Rescuing Species" article by Michelle Nijhuis, Orion Magazine, May/June 2008.
    A lengthy and elegant feature article that explores the human side of the controversy over assisted migration, with Torreya taxifolia providing the focal point, pro and con, and with actions by the citizen group Torreya Guardians stirring the brew. Comments page accessible through the foregoing link to Orion magazine.

  • "Multidimensional Evaluation of Managed Relocation" 22-author paper by David M. Richardson et al, Proceedings National Academy of Sciences, May 2009.
    ABSTRACT: Managed relocation (MR) has rapidly emerged as a potential intervention strategy in the toolbox of biodiversity management under climate change. Previous authors have suggested that MR (also referred to as assisted colonization, assisted migration, or assisted translocation) could be a last-alternative option after interrogating a linear decision tree. We argue that numerous interacting and value-laden considerations demand a more inclusive strategy for evaluating MR. The pace of modern climate change demands decision making with imperfect information, and tools that elucidate this uncertainty and integrate scientific information and social values are urgently needed. We present a heuristic tool that incorporates both ecological and social criteria in a multidimensional decision-making framework. For visualization purposes, we collapse these criteria into 4 classes that can be depicted in graphical 2-D space. This framework offers a pragmatic approach for summarizing key dimensions of MR: capturing uncertainty in the evaluation criteria, creating transparency in the evaluation process, and recognizing the inherent tradeoffs that different stakeholders bring to evaluation of MR and its alternatives. [Ed. note: This paper is the product of the Managed Relocation Working Group project. Details of three species-specific case studies, including pro and con managed relocation of Florida Torreya, are described in a supplementary pdf. Click the url at the bottom right of page 1 of the pdf of the main paper.]

    Read the National Science Foundation press release of the above article, where you can also access short VIDEOS of Jessica Hellmann talking about the importance of managed relocation.


    ASSISTED MIGRATION FOR FORESTS OF NORTH AMERICA

    Best Review Article:

    SOCIETY OF AMERICAN FORESTERS REVIEW ARTICLE (2013): "Preparing for Climate Change: Forestry and Assisted Migration", by Mary I Williams and R. Kasten Dumroese, in Journal of Forestry, July 2013.

    SUMMARY QUOTE: Climate is changing at a faster pace than natural plant migration, which poses a major challenge to forest management and conservation. We can draw from a century of forest research and management to curtail losses in forest growth, productivity, and conservation by implementing strategies, such as assisted migration. Even though we have seed transfer guidelines and seed zones for many commercial tree species, we lack clear, standard operating procedures to determine how, when, and where to implement movement. Movements outside current guidelines and zones may run afoul of legal restrictions and state and federal directives, but facilitating climatic adaptation through assisted migration has the potential to preserve forest health and productivity, subsequently maintaining ecosystem services, such as carbon sequestration, soil and water conservation, timber, and wildlife habitat. Our review and presentation of current information for researchers, foresters, landowners, and nurseries provides components to consider in their climate change adaptation plans.

    Editor's Note: The above article is ideal for learning the historical and policy reasons why commercial and public foresters are generally accepting of and at ease with "assisted migration" strategies for coping with anticipated climate change, as applied to populous (and also commercial) tree species. In contrast, resource managers responsible for endangered species and restoration of botanically targeted conservation lands are far more cautious about adopting (even considering) assisted migration as a management tool.

    See also Williams and Dumroese 2013, "Climatic Change and Assisted Migration: Strategic Options for Forest and Conservation Nurseries". Also, "Placing Forestry in the Assisted Migration Debate", by John H. Pedlar et al, 2012, Bioscience. Also: "An Overview of Some Concepts, Potentials, Issues, and Realities of Assisted Migration for Climate Change Adaptation in Forests", by Louis R. Iverson et al., 2013. This latter document distinguishes between two forms of assisted migration: Species Rescue AM v. Ecosystem Services AM; it concludes that the latter is less problematic and has "been underway for centuries" by foresters. (Example of black oak AM into northern Wisconsin under consideration to cope with expected climate change.)

       In 2008, the Climate Change Resource Center of the U.S. Forest Service assembled a dozen research foresters at the leading edge of translating climate change science into "adaptation" responses for forest managers. These scientists delivered excellent short talks captured on video. The result is a superb, free online learning tool: ADAPTING TO CLIMATE CHANGE: A Short Course for Land Managers". "Assisted Migration" as an important adaptation strategy for foresters is specifically mentioned by Constance Millar. Similarly, Jill Baron encourages experimentation (in which lack of success in small-scale adaptation projects would be regarded as helpful learning experiences, not failures).

    MAPS OF USA FOREST TREE SPECIES FUTURE RANGES: "Plant Species and Climate Profile Predictions". Highly detailed online maps to compare current, 2030, 2060, and 2090 range predictions for 76 species of western USA trees. (Always click on the .png versions to see the maps.) For example, Alligator Juniper, now absent from Colorado, is expected to show up west of Denver in 2030. (How are they going to get there, as the closest current population is near Santa Fe NM?)

    PALEOECOLOGICAL DISTRIBUTION OF E. NORTH AMERICA TREES: "Molecular Indicators of Tree Migration Capacity Under Rapid Climate Change", by McLachlan et al., in Ecology, 2005. CONTENT: Excellent review of paleocological investigations using paleo-pollen, macrofossils, and genetic data to ascertain (a) locations of glacial refuges of N.A. temperate trees during the last glacial maximum, and (b) the northward path and speed of movement as the peak glacial episode began to wane some 18,000 years ago. Interestingly, both of those forms of data indicate speed of northward return (at least for maple and beech tree genera) far faster than observation of current dispersal would otherwise suggest.

    HOW NORTH AMERICAN TREES SPECIES AND BIOMES SHIFTED FROM PEAK GLACIAL TO WARM TIMES: "Late-Quaternary Vegetation Dynamics in North America: Scaling from Taxa to Biomes" - John W. Williams et al., Ecological Monographs, 2004. Excerpts: "This paper integrates recent efforts to map the distribution of biomes for the late Quaternary with the detailed evidence that plant species have responded individualistically to climate change at millennial timescales. We show how the individualistic shifts in range and abundance for plant taxa scale upward to cause (1) compositional shifts within plant communities, (2) appearances and disappearances of novel plant associations, and (3) changes in the position, area, composition, and structure of biomes. Modern associations such as Fagus-Tsuga and Picea-Alnus-Betula date to the early Holocene, whereas other associations common to the late-glacial period (e.g., Picea-Cyperaceae-Fraxinus-Ostrya/Carpinus) no longer exist."

    Potential Impacts of Climate Change on the Distribution of North American Trees - Daniel W. McKenney et al., BioScience, December 2007. Excerpt: "The mean centers of future climate envelopes are predicted to shift northward by 6.4 and 3.0 degrees latitude (i.e., roughly 700 km and 330 km) on average under the full-dispersal and no-dispersal scenarios, respectively (figure 2). The smaller northward shift shown by the no-dispersal scenario is not surprising given that, for this scenario, northward shifts are constrained by the northern edge of the current CE. However, the shifts predicted under the full-dispersal scenario are indeed drastic. The 25 tree species showing the greatest latitudinal shifts are listed in table 2. With the exception of white alder (Alnus rhombifolia), a western species, all of these species exhibit an extensive distribution in the southeastern quadrant of the continent, generally ranging north to the Great Lakes region. By the end of this century, the CE for most of these species is predicted to shift into northern Ontario and Quebec — in many cases to Hudson Bay. Results for the entire 130 tree species (and others) can be viewed at http://planthardiness.gc.ca/."

    NOTE: Easy-to-use USFS webpage of maps imaging current and climate-shifted ranges of 134 tree species in eastern North America: Climate Change Tree Atlas interactive site.

    CANADA: The government of Canada (Natural Resources Canada) and the Canadian Forest Service each are moving forward with strategies for adapting forests and forest resources to anticipated climate change. Natural Resources Canada maintains a webpage on "Assisted Migration", which as of mid 2013 includes these excerpts: "Forests are climate sensitive, and a range of climate change impacts are already evident across Canada. Trees appear to be responding to warming temperatures by dispersing into more climatically suitable habitats. However, some populations will be unable to keep up with the rapid rate of environmental change. Numerous adaptation options are being considered as ways to maintain the biodiversity, health and productivity of Canada's forests under continued climate change. One option that is of increasing interest is 'assisted migration,' the human-assisted movement of plants or animals to more climatically suitable habitats. . . British Columbia has extended seed transfer zones 200 metres higher in elevation for most species, and introduced new policy to allow the planting of western larch outside of its previous range. Alberta has extended seed transfer zones 200 metres higher in elevation and 2 degrees of latitude northward for most species. And Quebec has incorporated the risk of climate change maladaptation into seed transfer functions, planting seed mixtures composed of local and more southern seed sources in some regions.

    THREE CATEGORIES OF ASSISTED MIGRATION are identified:

  • Assisted population migration: The human-assisted movement of populations within a species' established range. (lower risk)
  • Assisted range expansion: The human-assisted movement of species to areas just outside their established range, facilitating or mimicking natural range expansion (intermediate risk)
  • Assisted long-distance migration: The human-assisted movement of species to areas far outside their established range, beyond areas accessible through natural dispersal. (higher risk)
  • Canadian Forest Service Publications:
  • Placing forestry in the assisted migration debate 2012
  • Why we disagree about assisted migration: ethical implications and the future of Canada's forest 2011
  • Assisted migration: Introduction to a multifaceted concept 2011
  • The implementation of assisted migration in Canadian forests 2011
  • Review of science-based assessments of species vulnerability: contributions to decision-making for assisted migration 2011. EXCERPT
    "Recently, many tools have been developed for assessing species-specific vulnerability to climate change. These tools are question-based assessments that consider multiple criteria for individual species; the criteria are related to exposure and sensitivity to climate change. The following tools are discussed in relation to their use in Canada: (1) the NatureServe Climate Change Vulnerability Index; (2) the System for Assessing Vulnerability of Species to Climate Change (SAVS); (3) the Forest Tree Genetic Risk Assessment; (4) the Index for Predicting Tree Species Vulnerability; (5) ecological standards developed for the assisted migration for Torreya taxifolia; and (6) the Seeds of Success Program. These tools can all be applied to different forest species and they vary in such areas as their species-specific evaluation criteria, means for addressing uncertainty, and the integration of climate change models."

    BRITISH COLUMBIA : Re: "Assisted Migration Adaptation Trial (AMAT)" in British Columbia Content: "Can a tree native to coastal British Columbia, given climate change, flourish in Fort Nelson? Can a tree native to the Interior live prosperously on Vancouver Island? Those are questions Greg O'Neill hopes to find answers for. O'Neill is a geneticist with Vernon's Kalamalka Forestry Centre, and is overseeing forestry's biggest climate change research trial in North America." Note: O'Neill and other foresters in British Columbia may be the furthest along of anyone in terms of already doing assisted migration of plants and on a massive scale, though it is mostly at the level of reseeding logged lands with seedstock drawn from populations of the same species lower in altitude or latitude.
       What O'Neill and colleagues are doing in British Columbia can be learned in the most detail in this article published in the scientific journal Nature on 18 June 2009. You can access the PDF here: "Forestry: Planting the Forest of the Future". See also a transcript of a Canadian television documentary on O'Neil's work with assisted migration for British Columbia forest tree species. Also, O'Neill is a coauthor of the 2011 paper by Leech et al.: "Assisted Migration: Adapting Forest Management to a Changing Climate". See also the 2013 AMAT bulletin.
       Meanwhile, in the USA, a US Forest Service report, 2009 Science Accomplishments of the Pacific Northwest Research Station includes this: "To test the viability of assisted migration, researchers planted seedlings from locations throughout western Oregon and Washington and northern California at nine sites in western Oregon and Washington. Responses of the different seed sources will be evaluated relative to test site environments and the environments of the seed sources." Page 49 of Part 2 PDF
       Also see a cautionary comment published in BC Forest Professonal, which includes "Growing taller and being more resistant to two diseases in three years does not mean that one population is better adapted to an environment than another. What will happen during the rest of the cottonwood clones' lifetimes? There could be an unseasonal frost or a pathogen that is adapted to attacking mature black cottonwood, killing a large proportion of the assisted southern population, while these trees focus their energy budget on growth at the cost of decreased defenses." Also see 2009 "Climate change and Canada's forests: from impacts to adaptation".
       Also see, "Climate Change to Drive Lodgepole Pine Trees from British Columbia", 1 March 2011 Vancouver Sun; "Whitebark Pine (Pinus albicaulis) Assisted Migration Trial"; "Whitebark Pine Assisted Migration Trial at Blackcomb site in B.C."; "Assisted Migration for Larch" (see also a 2011 Discovery Magazine article on the larch project: "The Transplanted Forest: A Bold Experiment in Preemptive Climate Adaptation"; "Moving Trees Helps Prepare for Climate Change", Scientific American 24 August 2011; "Assisted Migration Vital, Researcher Says" (Sally Aitkin), 7 November 2012; "Assisted migration to address climate change: recommendations for aspen reforestation in western Canada" (L.K. Gray et al, in Ecological Applications, 2011).

    NOTE: A key, lengthy "discussion paper" was published in 2011 in the BC Journal of Ecosystems and Management: "Assisted Migration: Adapting forest management to a changing climate" by Leech, Almuedo, and O'Neill.

    ONTARIO: in May 2011, the Canadian province of Ontario published a detailed scholarly bibliography of papers pertaining to climatic needs and adaptability of FOREST TREES IN ONTARIO, CANADA. Downloadable in PDF, the title is: "Assessing assisted migration as a climate change adaptation strategy for Ontario's forests: Project overview and bibliography"; same reported updated in 2014.

    U.S. FOREST SERVICE: A 2009 article, "Genetic Options for Adapting Forests to Climate Change", by Brad St. Clare and Glenn Howe (USFS), published in the Jan/Feb 2009 issue of Western Forester. Michelle Nijhuis posted a review article in Nature (Sept 19, 2012) about southwestern USA massive forest fires leading toward replacement of conifer trees by more drought-adapted shrubs and scrub oak — and how some forest managers already are replanting with lower-elevation and warm-adapted species as a "bridge to the future.": "Forest Fires: Burn Out". NOTE: 21 February 2013 the "Western Forestry and Conservation Association" held a conference entirely on "Assisted Migration: A Primer for Reforestation and Restoration Decision Makers". Also see 2012 "Determining suitable locations for seed transfer under climate change: a global quantitative method" - (excerpt) "Changing climate conditions will complicate efforts to match seed sources with the environments to which they are best adapted. Tree species distributions may have to shift to match new environmental conditions, potentially requiring the establishment of some species entirely outside of their current distributions to thrive. Even within the portions of tree species ranges that remain generally suitable for the species, local populations may not be well-adapted to altered local conditions."

    MINNESOTA: 2010 Minnesota DNR article, "Trees Fit for the Future", with tagline: "The boreal trees in our north woods today might not survive in a warmer climate. Researchers are trying to figure out which species will be most likely to succeed in forests of the fast-approaching future." THE NATURE CONSERVANCY "Climate Change Adaptation Case Study: Updating Northeast Minnesota's Forest Management Strategies" (2011) Excerpt: "Recent research findings from The Nature Conservancy in Minnesota and University of Wisconsin- Madison (Ravenscroft et al. 2010) show that forest composition in Northeast Minnesota is projected to change in the next 200 years. Loss in overall forest complexity and an increase in maple species are dominant characteristics of this projected change. Findings also show that over the long term, climate change may be working in direct opposition to current ('climate-uninformed') restoration management actions. Forest management in Minnesota has been focused on restoring boreal species. Recent research suggests that these same species are also unlikely to survive in a changed climate. A new, 'climate smart' strategy will manage for a larger diversity of tree species, allowing opportunity for the best-suited species to thrive under changed climate conditions and thus sustain an adapted future forest. . . . As noted by Miller and Woolfenden (1999) over a decade ago, the work in Ravenscroft et al. (2010) demonstrates that rapid climate change poses serious questions to the practice of using historical data to develop management plans when we know that future climates will significantly differ from past climates. These results suggest that new approaches to forest management, that facilitate adaptation to new climates, may be needed to maintain functional forest ecosystems."
         Note: See a superb, long popular article on this assisted migration action in a 2013 issue of the Minneapolis Star Tribune: "Saving the Great North Woods". Excerpt: "Driven by a warming climate, scientists predict, the [boreal forest in NE Minnesota] will soon follow the glaciers and retreat north by as much as 300 miles in the next century. Much of northern Minnesota, they say, will become open savannas like those in Nebraska and eastern Kansas — with grasses and brush, a few scattered trees, and domes of bare rock rising from the ground.

    MAPLE TREES: March 2012 news article: "Climate change could wreak havoc on maple syrup industry". Excerpt: "According to The Maple Daily, a news site dedicated to maple syrup, sugar maple trees now release their sap about 8.2 days earlier in the year and stop producing it 11.4 days earlier, resulting in a total of about 10 per cent loss in the duration of the maple production season . . . There is currently a debate as to whether forestry experts should be stepping in and taking action in the form of something like an assisted migration, moving trees to a more northern climate to protect them in a careful and controlled way, but like many other aspects of the industry, there is a lot of uncertainty."

    YELLOW CEDARS IN COASTAL ALASKA: February 2012 news article: "Death of Yellow Cedars Linked to Climate Change". Excerpt: "For more than a century, yellow cedars in Alaska and British Columbia have been dying, yet it was recently confirmed by U.S. Forest Service researchers that the cause was due to climate change. With climate change, there has been less snow on the ground to insulate the shallow roots from extreme temperatures. And with less snow on the ground, frozen roots have led to the decline of 60 to 70 percent of trees covering 600,000 acres in Alaska and British Columbia. Researchers also believe that yellow cedars may thrive in areas outside of where it has already migrated, leading to the hope that assisted migration may restore the dwindling population of these trees. However, there is also concern that assisted migration may cause yellow cedars to become an invasive species. Nevertheless, a trial planting of yellow cedars in Yakutat has been successful with a first-year survival rate of more than 90 percent." See also: "Research confirms warming for yellow cedar death"

    NON-NATIVE LODGEPOLE PINE PLANTED ON KENAI PENINSULA (ALASKA) TO REPLACE NATIVE SPRUCE DEVASTATION BY CLIMATE-CAUSED SPRUCE BEETLE ERUPTION: Although not called "assisted migration", this intentional use of a more warm-adapted tree species (native to the dry northern Rocky Mountains, occurring naturally at lower elevations to the spruce zones on mountain slopes) is a clear example of foresters drawing upon a more southerly species native to the continent to replace forest dominants that are no longer viable, given the climate shifts already impacting Alaska. See: "Alaska: Across the Wildest State, Climate Change Threatens Many Species and Habitats", USF&WS June 2011.

    REDWOOD TREES NORTH TO OREGON - David Milarch has been collecting branchlets from some of the "champion" trees of various species, especially in the USA. Because redwoods resprout from the base for many decades after the trunk is cut, he has collected clones of some of the biggest (long cut) specimens of historic times — and he is planning now to plant some of those clones "in areas that might be safer for the trees if the globe heats up, a process known as assisted migration." This was reported in The Oregonian ,"Ancient redwoods, giant sequoias to be 'archived' on Oregon coast", 27 Nov 2012.

    PINE TREES IN NEW JERSEY THREATENED BY NATIVE PINE BEETLE DUE TO WARMER WINTERS - "In New Jersey Pines, Trouble Arrives on Six Legs", 1 December 2013 report in New York Times. Excerpt: In an infestation that scientists say is almost certainly a consequence of global warming, the southern pine beetle is spreading through New Jersey's famous Pinelands. It tried to do so many times in the past, but bitterly cold winters would always kill it off. Now, scientists say, the winters are no longer cold enough. The tiny insect, firmly entrenched, has already killed tens of thousands of acres of pines, and it is marching northward. Scientists say it is a striking example of the way seemingly small climatic changes are disturbing the balance of nature. They see these changes as a warning of the costly impact that is likely to come with continued high emissions of greenhouse gases. The disturbances are also raising profound questions about how to respond. Old battles about whether to leave nature alone or to manage it are being rejoined as landscapes come under stress.


          
  • VIDEO: Climate Change Prompts Tree Deaths: Australia and the World (2012)

    11-minute video of 2012 produced by Australian television. Superb introduction to how increases in heat and drought contribute to tree deaths of an unprecedented scale. This video focuses on Australia, but also looks at the western USA, the Amazon forest, and elsewhere. The implications: Trees with slow natural rates of dispersal (anything other than wind-blown seeds) will require human-assisted migration of more heat-adapted populations of the same species or altogether different species.


  •       
  • VIDEO: Whitebark Pine Assisted Migration Trial in Canada & Alaska (2012)

    by Sally Aitken. Key topics include:

    26:52 - assisted migration section begins

    51:08 - the polarized debate on assisted migration

    56:03 - moving whitebark pine beyond its current range

    01:01:21 - risks of action v. inaction


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  • VIDEO: Greater Yellowstone Research: Whitebark Pine and Clark's Nutcracker Mutualism (2012)

    12-minute video of fieldwork by Taza Schaming, with excellent visuals of dead and dying Whitebark Pines and the key role played by Clark's Nutcracker in prying open the cones and then burying the seeds.


  •       
  • VIDEO: Whitebark Pine Ecology: Management of an Ecosystem in Decline (2012)

    38-minute video of 2012 illustrated talk by Dan Reinhart, ecologist of Yellowstone National Park. By clicking left, you will begin at 08:48 timecode, where the talk begins.


  • "Assisted Colonization: Moving Species for Conservation Purposes" undated website announcement of Conservation Breeding Specialist Group (CBSG), affiliated with the IUCN
    "IUCN has requested a review and update of its policies on this topic, with the aim of having a comprehensive IUCN position for submission at the 2012 World Conservation Congress. Accordingly the SSC has established the RSG-ISSG Task Force on Moving Species for Conservation Purposes. The lead person in this task force is Mark Stanley Price. Mark will convene a working group to discuss that scale, scope and terminology around this initiative and to gather answers to the questions: (1) How, where and for what do the benefits and risks of assisted colonization or conservation introduction compare favorably to doing nothing to assist species vulnerable to extinction? (2) What taxa of plants and animals do participants feel are the best bet for assisted colonization? and (3) What should be done to test some hypotheses?

  • "Relocating Animals to Safer Climes" journalist report by Reena Amos Syes, Emirates Business, 6 June 2010.
    Focal species is the reintroduction of extirpated Oryx to its homeland in Oman and how that will be affected soon by the scheduled release in 2012 of international guidelines for translocation of species in response to climate change by the "Species Survival Commission." Quotes fr Dr Mark Stanley Price, incl: ""That is why chosen scientists from all over the world have been asked by the International Union for the Conservation of Nature and Natural Resources (IUCN), to set up a group to look at assisted colonisation globally. It wants us to set up guidelines for assisted animal colonisation and release new guidelines at the World Conservation Congress in 2012 in South Korea."

  • Rare S. Appalachian plant being tested for assisted migration Smith College News, 26 July 2010.
    Excerpts: Last fall, Kaila Matatt '10 joined Jesse Bellemare, assistant professor of biological sciences, on a five-year investigation into the success of relocating one plant, the Umbrella Leaf, to cooler climes. The native of southern Appalachia met the typical criteria of plants that are most in danger of extinction ‚Äď those with small geographic ranges and limited ability to disperse, she said. When Bellemare began the investigation in 2008, he sought and received approval to temporarily transplant the Umbrella Leaf to areas within state forests in Virginia, Maryland, Pennsylvania, New York and Massachusetts. He also identified three control sites within the native range to provide a comparison. Until the end of the project in 2013, the plants will continue to be monitored for germination and growth, as well as monitored for flowers and seeds, she said. After that, all of the transplants will be removed.

  • "Deciding when to move plants and animals to save them from global warming" journalist report by Cassandra Brooks, Stanford Report, 5 June 2009.
    Report of 25 May 2009 multi-author paper in Proceedings of the National Academy of Sciences, which proposes a new management tool for choosing which species are most viable for relocation based on a series of social and ecological criteria—for example, how much is known about the biology, geographical distribution and the ecological uniqueness of the species, as well as how easy they are to catch and move. Social factors, such as cultural importance, financial impact and even the laws and regulations regarding the species, also are considered. Partially funded by the National Science Foundation (NSF), the working group is co-led by Jessica Hellmann and Jason McLachlan of the University of Notre Dame, Dov Sax of Brown University, and Mark Schwartz of the University of California at Davis. David Richardson of Stellenbosch University in South Africa led the writing of the paper. See also this Press Release on the paper.

  • "Between the Devil and the Deep Blue Sea" science journalist article by Jim Robbins, Conservation, Apr-Jun 2009.
    Arresting article on the extent and speed of the paradigm shift in conservation away from traditional "preservation" modes of intervention in behalf of biodiversity to "adaptationist" modes, including the growing acceptance of "assisted migration" as a management tool to cope with globally and regionally shifting climates. Superb coverage of the wrenching change of heart (and financial focus) for conservation programs rooted in "restoration" to practically address the irreversible shifts in climate now inarguably underway. "Managed retreat" (term used by conservation biologist Reed Noss, who argues for an overhaul of Everglades restoration policy) now joins "assisted migration" in the growing panoply of conservation terms and tools.
    Note: Serious students of this topic may wish to start with the paper by Shirey and Lambert (below), as it is an excellent summary of the ecological science, the actions-to-date, the law, and the regulatory options, and it was clearly written from an objective position, neither pro nor con.

  • "Assisted Colonization Under the U.S. Endangered Species Act" by biologists Patrick D. Shirey and Gary A. Lamberti, in Conservation Letters, February 2010 3(1): 45-52 [full text in PDF online free access]
    "The paper represents a call to arms or a call to caution, depending on your perspective," says Gary Lamberti, the chair of the Department of Biological Sciences who is Shirey's advisor and co-author of the article. "When we're thinking about moving organisms around because of climate change or other environmental factors, we need to think about the legal framework that will enable or not enable us to do that. What Patrick did with his analysis was encourage policy makers and legal scholars to examine the statutes before we reach a crisis point." (quotation drawn from the author's online announcement of the paper). Here are several important legal conclusions made in the paper:
        "Current agency regulations impede alternative strategies such as assisted colonization for endangered animals, but do not impede assisted colonization of endangered plants." (p. 3) "On its surface, the statutory language of the ESA appears to provide the legal framework for allowing assisted colonization of endangered populations to new habitats primarily under Section 10(j), the experimental population provision" (p. 3) "In 1982 additions to the ESA, Congress sought to restrict the use of the experimental population provision as a means of removing protection from species and thus imposed procedural limits. Those limits, however, did not restrict the power of the agency to release species into suitable areas without considering historical distribution. The USFWS can authorize release outside the current range if 'release will further the conservation of such species' (citation). However, in promulgating regulations to implement the experimental population provisions, the USFWS added a geographic restriction in 1984 that prohibits an experimental population from being introduced outside the historic range, 'absent a finding. . . in the extreme case that the primary habitat of the species has been unsuitably and irreversibly altered or destroyed' (citation) (p. 5) "Perhaps the most successful case of assisted colonization of a plant listed under the ESA is the Virginia roundleaf birch (Betula uber). The first translocation of roundleaf birch occurred after the species was rediscovered in 1975 as a population of 41 trees (59 FR 59173). After the round-leaf birch was listed in 1978, the USFWS encouraged its distribution to conservation organizations and individuals (59 FR 59173). Despite protection of its habitat by agencies and landowners, the natural population of round-leaf birch declined to eight trees in 2003 (www.fws.gov/northeast/pdf/vabirch.pdf). However, because assisted colonization established 20 populations on U.S. Forest Service land, the USFWS reclassified roundleaf birch from endangered to threatened in 1994 (59 FR 59173)." (p. 6) "Regulatory restrictions placed on assisted colonization might be lesser obstacles to overcome than political and scientific resistance. Political opposition can include concern over costs of managing populations, resistance of landowners and local governments to introducing endangered species, and concern over species invasiveness. The threat of invasive species, in particular, raises legitimate scientific concern about assisted colonization." (p. 6) "Assisted colonization could be a viable management option to offset the human-caused and inseparable problems of habitat fragmentation and rapid climate change." (p. 7)

    To see what is going on in Europe on this topic, see pp 42-43 of Convention on the Conservation of European Wildlife and Natural Habitats: Standing Committee Report of November 2009.

  • "Anachronistic Fruits and the Ghosts Who Haunt Them", by Connie Barlow, 2001, in Arnoldia Magazine.
    Note: This article may be the first published advocacy of translocation (assisted migration) of Torreya taxifolia. The last section of the article is titled, "Is the Endangered Torreya Tree Anachronistic?". Barlow concludes, "Transplantation across great distances is an uncommon and controversial technique for biodiversity conservation today. But as the greenhouse effect ratchets up temperatures and reroutes rainfall, and as botanical preserves become even more isolated islands in a sea of human development, long-distance transplantation will become the norm. If gardening a few local patches of endangered plants is tough today, it's going to get a lot tougher when, like it or not, we become gardeners of the planet. Helping plants track climate change from one patch of habitat to another will be a routine tactic for conserving biodiversity decades hence. Is it too early to begin now with florida torreya?"

    VIDEO: First assisted migration action: Torreya

       Connie Barlow presents the rationale for advocating "assisted migration" northward to help an endangered conifer tree, Florida Torreya (Torreya taxifolia), recover from otherwise certain extinction. Barlow's talk was filmed in 2004 — the same year that she and Paul S. Martin co-authored an advocacy piece, "Bring Torreya Taxifolia North Now," published in Wild Earth magazine. 2004 was also the year that Connie coordinated the formation of and created a website for Torreya Guardians, torreyaguardians.org

    Four years after this talk was filmed, Barlow and other Torreya Guardians" legally planted 31 nursery-grown seedlings of Torreya taxifolia in two forested plots of private land in the mountains of North Carolina. This action is recognized as the first intentional "assisted migration" for a plant species in the USA in direct response to climate change.

  • "Bring Torreya Taxifolia North — Now", by Connie Barlow and Paul S. Martin, 2004, in Wild Earth Magazine.
    Note: This paper is the first full advocacy of assisted migration for Torreya taxifolia. The authors conclude, "'Left behind in near time' may thus be a syndrome that applies to a number of extinct, imperiled, and soon-to-be imperiled plants, and perhaps to small, isolated populations of species that are not themselves in danger of extinction. How might this awareness alter our conservation options as climate shifts? By assisting the migration of Torreya taxifolia now, we can help to shape a better next chapter for this beleaguered tree and, perhaps, many other plants."

  • "NASA: Climate Change May Bring Big Ecosystem Changes", press release, December 2011, Jet Propulsion Laboratory.
    Excerpts: By 2100, global climate change will modify plant communities covering almost half of Earth's land surface and will drive the conversion of nearly 40 percent of land-based ecosystems from one major ecological community type . . . Most of Earth's land that is not covered by ice or desert is projected to undergo at least a 30 percent change in plant cover - changes that will require humans and animals to adapt and often relocate. . . While Earth's plants and animals have evolved to migrate in response to seasonal environmental changes and to even larger transitions, such as the end of the last ice age, they often are not equipped to keep up with the rapidity of modern climate changes that are currently taking place. Human activities, such as agriculture and urbanization, are increasingly destroying Earth's natural habitats, and frequently block plants and animals from successfully migrating.

  • "The Hidden Battle Behind Formal Gardens", report by Paddy Woodworth, 10 July 2010, in Irish Tmes
    Excerpt: Perhaps the most radical update on the table now is the concept of 'assisted migration', a benign phrase that just might be the key to keeping many trees, shrubs and flowers in the landscape — and out of the chilled filing cabinets. But it is a concept that also raises as many problems as it proposes to lay to rest. As with animals, plants migrate to find the best living conditions, but plants do it slowly, over generations. Trees, with their very long life spans, are especially slow. Earthworms are sprinters by comparison. Ten thousand years ago, as the ice sheets retreated from the North American Midwest, trees migrated up the continent at the rate of about 100km per century, until the global climate settled into relative stability — the condition we thought of as normal until very recently. Global change models suggest that climate 'envelopes' will soon be moving north at speeds of 1,000km per century. So, if the models are right, this is a race that trees are certain to lose. . . Donnelly knows that the best outcome of assisted migration will involve the disintegration of cherished and valuable communities of plants and animals. Whatever novel communities will emerge may be poorer, or even richer, in biodiversity than what we know today, but they will certainly be different. However, he argues soberly that assisted migration must be among our options for "managing long-lived trees for an uncertain future". Restoration used to be about attempting to return ecosystems to a past (and more biodiverse) state, but the wild card of climate-change is pushing restoration science towards the creation of new systems, with the proviso that maintaining biodiversity is still the target. EDITOR'S NOTE: A 2011 survey of the actual movement poleward or altitudinally by 1,376 species found that the average rate was 10 miles per decade poleward and 40 feet per decade upslope, but the individual variation was quite wide. See "Climate Change: Species Climbing Higher and Migrating North, Study Says".

  • "A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests", by Craig D. Allen and 19 other coauthors, 5 February 2010, in Forest Ecology and Management 259(4): 660-84.
    Excerpt from abstract: "Here we present the first global assessment of recent tree mortality attributed to drought and heat stress. Although episodic mortality occurs in the absence of climate change, studies compiled here suggest that at least some of the world's forested ecosystems already may be responding to climate change and raise concern that forests may become increasingly vulnerable to higher background tree mortality rates and die-off in response to future warming and drought, even in environments that are not normally considered water-limited. This further suggests risks to ecosystem services, including the loss of sequestered forest carbon and associated atmospheric feedbacks."

    For superb popular coverage of this article and the underlying forest-dieoff phenomenon, read the online report by Jim Robbins dated 15 March 2010: "What's Killing the Great Forests of the American West?".

  • "Naturalness and Beyond: Protected Area Stewardship in an Era of Global Environmental Change", by David N. Cole and 15 other coauthors, 2008, in The George Wright Society Forum 25:36-56.
    Highly useful integrative paper geared for managers of natural lands that examines the need for new philosophical and practical perspectives on management of parks and wilderness areas today, especially given rapid climate change. "Assisted migration" is discussed in this report, but in the much wider context, thus making this paper a key reading for background perspective as well as precise philosophical and management options that supplement the criterion of "natural" with more precise understandings of "historical fidelity," biodiversity conservation," "resilience," and "ecological integrity."

  • "Deep-Time Lags: Lessons from Pleistocene Ecology" by Connie Barlow, in Gaia in Turmoil: Climate Change Biodepletion, and Earth Ethics in an Age of Crisis, edited by Eileen Crist and H. Bruce Rinker, 2009, MIT Press.
    Torreya Guardians founder Connie Barlow contributed a chapter on the importance of a "deep time" perspective for conservation biologists and biodiversity activists coming to grips with the extinction crisis in an age of rapid climate change. The plight of Torreya taxifolia and the work of Torreya Guardians are used as the key example of "Assisted Migration in a Time of Global Warming".

  • "Paleoecology and 'inter-situ' restoration on Kauai, Hawaii" by David A. Burney and Lida Pigott Burney, in Front Ecol Environ 2007; 5(9): 483-490, doi 10.1890/070051.
    Review paper of ongoing work on Kauai that actively uses a pre-historic baseline (prior to first human arrival one- or two-thousand years ago) for developing standards for plant restoration ecology on the island. A great example that there is a continuum between "historic" and "Pleistocene" standards for "restoration" and "rewilding." A must-read for those who cling to "historic native range" standards for opposing on principle "assisted migration."

  • "Snakes Struggle to Keep Pace with Climate" news story in Futurity, (13 December 2011)
    Summary of PLoSOne paper, "Pleistocene Climate, Phylogeny, and Climate Envelope Models: An Integrative Approach to Better Understand Species' Response to Climate Change", by A. Michelle Lawing and P. David Polly, 12/2/11. Quotes from the news summary: "We find that, over the next 90 years, at best these species' ranges will change more than 100 times faster than they have during the past 320,000 years," says lead author Michelle Lawing, a doctoral candidate in geological sciences and biology at Indiana University. "This rate of change is unlike anything these species have experienced, probably since their formation." . . . Snakes won't be able to move fast enough to keep up with the change in suitable habitat, the study suggests. Creation of habitat corridors and managed relocation may be needed to preserve some species.

  • "A Home from Home: Saving Species from Climate Change" news story by Suzanne Goldenberg in Guardian.co.uk, (12 February 2010)
    Conservation biologist Camille Parmeson is profiled in her advocacy for translocation of species threatened by climate change. She is quoted, "It doesn't make any sense to say it's OK for the shipping industry and the transport industry to accidentally move stuff around, for the aquarium trade to move stuff around, for the garden trade to move stuff all over the place, but that it's not OK for a conservation biologist who is desperately trying to save a species from extinction to move it 100 miles. Come on, we have mucked around with Earth to such a degree that I think it's a ridiculous argument.''

  • "Analysis of climate paths reveals potential limitations on species range shifts" by Regan Early and Dov Sax, Ecology Letters (29 September 2011)
    From press release: In a new study based on simulations examining species and their projected range, researchers at Brown University argue that whether an animal can make it to a final, climate-friendly destination isn't a simple matter of being able to travel a long way. It's the extent to which the creatures can withstand rapid fluctuations in climate along the way that will determine whether they complete the journey. Regan Early and Dov Sax examined the projected "climate paths" of 15 amphibians in the western United States to the year 2100. Using well-known climate forecasting models to extrapolate decades-long changes for specific locations, the researchers determined that more than half of the species would become extinct or endangered. The reason, they find, is that the climate undergoes swings in temperature that can trap species at different points in their travels.
        Confronted with these realities, Early and Sax say wildlife managers may need to entertain the idea of relocating species, an approach that is being hotly debated in conservation circles. "This study suggests that there are a lot of species that won't be able to take care of themselves," Sax said. "Ultimately, this work suggests that habitat corridors will be ineffective for many species and that we may instead need to consider using managed relocation more frequently than has been previously considered." news report on; illustrated report on.

  • "Taking Stock of the Assisted Migration Debate" by Nina Hewitt et al, Biological Conservation (volume 144, pages 2560-72), 2011.
    Lead author Dr. Nina Hewitt (a biogeographer and IRIS Senior Fellow) and her coauthors conducted a bibliometric study of the existing academic literature on assisted migration, classifying it in terms of study methods, geographic and taxonomic (species) focus, and degree of knowledge transfer from the natural sciences to other academic disciplines and non-academic sectors. They show that the volume of scholarly writing on assisted migration has exploded in the past three years, addressing a wide range of regions and species. The article's main contribution is to analyze the scholarly debate about the desirability and feasibility of assisted migration as a response to climate change. At a general level, a majority of the papers reviewed were generally supportive of using or at least considering assisted migration, but a closer examination shows that the debate is intensifying. NOTE: A news article on this report quotes Hewitt as saying, "With this paper, we were hoping to highlight the different sides of the debate so that scientists and policymakers can evaluate the risks and benefits and together make some progress so we don't get stuck in that paralysis. . . What I found was that the debate seemed to be stuck around what we call 'other issues' — neither direct risks nor benefits to implementing a particular assisted migration, but rather, counter arguments to the opposite side of the debate. These counter arguments need to be distinguished from direct risks and benefits because they can't provide justification for scrapping or adopting the policy."

  • "Location, Location, Location: Assisted Migration May Be Coming Closer to a Reality as a Response to Climate Change" by Yee Huang in CPR Blog, (01 February 2011)
    "In the UK, the Environment Agency is "exploring" moving thousands of vendace and schelly, both freshwater white fish, from the northern Lake District in England to cooler waters in Scotland. While still in the planning stages, this strategy represents a remarkably specific and dramatic response to climate change." Includes link to the UK study mentioned.

  • "Assessing the potential for urban trees to facilitate forest tree migration in the eastern United States," C.W. Woodall et al in Forest Ecology and Management 259 (2010) 1447-1454
    "The goal of this study was to compare tree species compositions in northern urban areas to tree compositions in forestland areas in the eastern U.S. as an indicator of the potential for urban trees to facilitate future forest tree species migration. Results indicated that a number of tree species native to eastern U.S. forests of southern latitudes are currently present in northern urban forests."

  • "Conservation Biology: The End of the Wild" by Emma Marris, Nature 12 January 2011, 469:150-52
    "Climate change means that national parks of the future won't look like the parks of the past. So what should they look like? . . . [National Park Service director Jonathan] Jarvis has suggested the possibility of moving species outside their native ranges to give them a better chance of surviving — just not right away. "The big point here is that we are willing to face these questions," he says. "We are not afraid to talk about them."

    SEE ALSO an Dec 2010 online interview with NPS Director Jonathan Jarvis on climate change and park management, including "assisted migration".

  • "Climate Change Risks and Conservation Implications for a Threatened Small-Range Mammal Species" by Morueta-Holme et al., PLOS One29 April 2010
    "Here, we provide a detailed assessment of the climate sensitivity and potential distributional impacts of 21st century climate change for an illustrative endemic species limited to a restricted part of the Mediterranean region. This region is rich in endemic species and is expected to experience particularly severe global-change-driven biodiversity losses over the 21st century. The study species is the Iberian desman Galemys pyrenaicus (E. Geoffroy Saint Hilaire, 1811), a small semi-aquatic mammal endemic to the Iberian Peninsula.

  • "Big Moving Day for Biodiversity: A macroecological assessment of the scope for assisted colonization as a conservation strategy under global warming" by Jens-Christian Svenning, IOP Conf. Series: Earth and Environmental Science 8 (2009) 012017
    12-page report in PDF

  • "Wildlife Service Plans for a Warmer World" news report by Janet Fang, NatureNews Published online 17 March 2010 | Nature 464, 332-333 (2010) | doi:10.1038/464332a
    The report, a collaboration between the USFWS, the US Geological Survey, academics and a collection of environmental and wildlife groups, quantified the vulnerability of each species on the basis of its breeding behaviour, habitat, migratory pattern and ecological niche. George Wallace, vice-president for oceans and islands at the American Bird Conservancy in The Plains, Virginia, says the report shows that "we need to consider climate change as we continue conservation work into the future".

  • "Temperature-Dependent Sex Determination and Contemporary Climate Change" by N.J. Mitchella, F.J. Janzen. Journal: Sexual Development, published online, only abstract freely available (9 February 2010)
    Whether species that have persisted throughout historic climatic upheavals will survive contemporary climate change will depend on their ecological and physiological traits, their evolutionary potential, and potentially upon the resources that humans commit to prevent their extinction. For those species where temperatures influence sex determination, rapid global warming poses a unique risk of skewed sex ratios and demographic collapse. Here we review the specific mechanisms by which reptiles with temperature-dependent sex determination (TSD) may be imperilled at current rates of warming, and discuss the evidence for and against adaptation via behavioural or physiological means. We propose a scheme for ranking reptiles with TSD according to their vulnerability to rapid global warming, but note that critical data on the lability of the sex determining mechanism and on the heritability of behavioural and threshold traits are unavailable for most species. Nevertheless, we recommend a precautionary approach to management of reptiles identified as being at relatively high risk. In such cases, management should aim to neutralise directional sex ratio biases (e.g. by manipulating incubation temperatures or assisted migration) and promote adaptive processes, possibly by genetic supplementation of populations.

  • "Ecological History and Latent Conservation Potential: Large and Giant Tortoises as a Model for Taxon Substitutions" by Dennis M. Hansen et al. Ecography: 33: 272-84 (2010)
    This paper is listed here, as well as among the "rewilding" links at bottom, because while advocating carefully assessed and monitored "taxon substitutions" of tortoises (that is, re-introducing herbivorously similar large and giant tortoises into landscapes, especially islands, where the endemic species were exterminated by humans or shifting sea levels within historic or prehistoric time), the authors also suggest that it would be helpful for the IUCN to include in its current work to develop express international guidelines for managing the need to engage in climate-induced "assisted migration/translocation" guidelines as well for "taxon substitutions": "Despite global potential for resurrecting lost species interactions and restore degraded ecosystem functions, taxon substitutions remain controversial. We suggest that a healthy debate on the applicability of taxon substitutions could be facilitated by including guidelines for them within an expanded IUCN species translocation framework. This would have the added benefit of promoting species interactions and functional integrity of ecosystems as integral parts of all translocation projects. Furthermore, conducting taxon substitutions and reintroductions within a proper experimental framework will facilitate the interpretation of ecosystem responses

  • "The Velocity of Climate Change" by Scott R. Loarie et al. Nature, 462, 1052-1055 (24 December 2009)
    Important scholarly/scientific work that results in an estimate of 1/3 mile per year on average of latitudinal shift in climate and only 8% of protected lands being large enough to include today's climate within its bounds in a century. The abstract only is available for free online, at the url above, but you can read a news report of it at Discovery News.

  • "From Reintroduction to Assisted Colonization: Moving along the Conservation Translocation Spectrum" by Philip J. Seddon, opinion article in Restoration Ecology 2010
    "Historic distribution records will always provide a good starting point for identifying translocation release sites, but global climate change and the dynamic nature of ecosystems mean that historical species ranges have only limited use. Other, even pre-historic reference points, and species-specific habitat suitability assessments should be considered.
        "Single-species conservation actions in the core of historic range will remain the backbone of many conservation efforts, but increasingly we need to adopt an ecosystem focus and consider the translocation of suites of species to restore key ecological functions. Ecological functions once performed by now-extinct taxa can be restored through the introduction of ecological replacements, which may themselves be threatened in their native range."

  • "Big Moving Day for Biodiversity? A macroecological assessment of the scope for assisted colonization as a conservation strategy under global warming" by Jens-Christian Svenning et al. IOP Conf. Series: Earth and Environmental Science, 8 (2009) 012017
    clip from ABSTRACT: "Our results suggest that there is substantial room for additional plant species across most areas of Europe, indicating that there is considerable scope for implementing assisted colonization as a proactive conservation strategy under global warming without necessarily implicating negative effects on the native flora in the areas targeted for establishment of translocated populations. Notably, our results suggest that 50% of the cells in Northern Europe, the likely target area for many translocations, could harbor at least 1/3 as many additional species as they have native species."

  • "Return of the Ericads: Students Dig and Reestablish a Prehistoric Species", by Michael Heim, Journal American Rhododendron Society, Winter 2010
    Michael Heim is a science teacher at Lac Courte Oreilles Ojibwe High School, Hawyard WI, whose students planted in May 2009 cloned cuttings from a very rare eastern native: the evergreen Box Huckleberry, Gaylussacia brachycera. The 2 page, photo-rich PDF of this article is a fascinating look at "rewilding" of an endangered species, based on a "deep-time" perspective in which "native" is regarded as including a plant's presumed preglacial regional distribution. In a March 5 comment posted on the Torreya Guardians site, Heim reports that he and his students have also planted cuttings from clones of Torreya taxifolia and Taxus floridana on the same tribal forest lands next to the school in northern Wisconsin, thus signifying another citizen-initiative of assisted migration, based on a deep-time understanding of native range.

  • "Assisted Colonization: Integrating Conservation Strategies in the Face of Climate Change", by Scott R. Loss et al., Biological Conservation, December 2010
    A 3-page comprehensive review of the major papers and arguments, primarily useful for all the linked references. It is too compressed to be useful for fully understanding the major implications. As with virtually all the published papers through 2010, the major argument against assisted migration is risk of invasiveness in its targeted new range. And as with all its predecessor papers cited, it fails to put this issue in the context of deep time: that is, it fails to recognize that species that may be considered for assisted migration are millions (even tens of millions) of years old, and have been moving vast distances independently of one another north and south and also up and down mountains throughout the significant climate shifts of the Pleistocene epoch, and before. This point is brought out in one key paper cited in this review article. It is the paper by Mueller and Hellman, 2008: "An Assessment of Invasion Risk from Assisted Migration", which concludes that N-S translocations of land species on the same continent pose relatively little risk, while moving crustaceans and fish between aquatic watersheds evidences a history of problems. The strongest advocacy of a deep-time perspective is by Connie Barlow of Torreya Guardians, in her 2005 paper (co-authored with Paul S. Martin): "Bring Torreya taxifolia North Now" and her 2011 onine piece: "Assisted Migration (Not Assisted Colonization) for Endangered Torreya".

  • "A Hunt for Seeds to Save Species, Perhaps by Helping Them Move" science journalist article by Ann Raver, New York Times, 9 November 2009.
    "Scientists from the [Chicago Botanic Garden] are sending teams out across the Midwest and West to the Rocky Mountains and Great Basin to collect seeds from different populations of 1,500 prairie species by 2010, and from 3,000 species by 2020. The goal is to preserve the species and, depending on changes in climate, perhaps even help species that generally grow near one another to migrate to a new range." "'We recognize that climate change is likely to be very rapid and that seeds only disperse a few hundred yards, half a mile at most, naturally,' said Kayri Havens, the botanic garden's director of plant science and conservation. 'They'll need our help if we want to keep those species alive.'"

  • "Assisted Migration of Plants: Changes in Latitudes, Changes in Attitudes" by Pati Vitt et al., Biological Conservation, 23 September 2009.
    Excerpt: "Intra-continental translocation has also proven an important conservation tool to help species escape diseases driving them to extinction in their native range. This includes numerous Australian species like Lambertia orbifolia (roundleaf honeysuckle), declining due to the devastating effects of Phytophthora cinnamomi (root rot fungus disease). For these species, translocation has been employed as a conservation measure since the mid-1990s (Cochrane, 2004), and in the United States, the formerly abundant Florida Torreya (Torreya taxifolia) has lost at least 98.5% of its former population size since the 1900s due largely to disease (Schwarz et al., 2000). Since 1989, ex situ collection and propagation, as well as translocation, have become key modes of conservation for the species. The Torreya Guardians, a group of citizens undertaking the translocation of the Florida torreya, now cite climate change as an additional rationale for movement of the species outside its historic range (Barlow and Martin, 2005), though the practice is not universally accepted (Schwartz, 2005; Ricciardi and Simberloff, in press).
        "Translocating plants is not without risk, the most problematic is the potential for a species to become invasive in its introduced range. Intercontinental movement of species has indeed resulted in problems with invasive species, but the vast majority of introduced species do not become invasive. It is estimated that less than 1% of species become invasive when imported to a new range (Williamson and Fitter, 1996), and only a small percentage of those (7.5% of invasives in the US) are a result of intra-continental introductions (Mueller and Hellmann, 2008). Most discussions of assisted migration in the context of climate change involve moving species relatively short distances poleward or higher in elevation within a continent, and many focus on species with limited dispersal ability which are less likely to become weedy (Rejmanek and Richardson, 1996). In many anthropogenically fragmented habitats, migration assistance in the form of short distance jump dispersal or corridor creation may be necessary for species to survive. These types of dispersal pathways are less likely to result in enemy release and biological invasion than are long distance and mass dispersal (Wilson et al., 2009).
        "We envision a future where well-conceived translocations of species may reduce the risk of extinction, as well as in- crease the number of potential taxa creating new assemblages in a fluid landscape responding to broad scale changes.
        "While we debate about whether and how to implement assisted migration strategies, species already at risk are being further stressed by the unpredictability of the environmental changes they are experiencing. For plants, at any rate, the solution seems clear: collect and bank them now, and then plan the implementation stage when it is appropriate. As Hunter (2007) points out: implementation of an ex situ conservation strategy is far less problem- atic for plants, and a great deal less expensive, than for other taxa of conservation interest.
        "Ultimately, implementation of assisted migration, or other large scale conservation mechanisms, will require reconciliation be- tween the hubris of being able to control nature, with the hubris that humans are somehow not a part of nature. Incorporating the newly emerging science of restoration genetics, and the lessons learned from both rare plant translocation experiments and the practice of restoration ecology will provide a road map for how to design assisted migration events. While natural communities of the future may not have current day analogs, our job is to ensure that they are as species-rich and genetically-diverse as possible."

  • "Climate Change Science Compendium 2009" by United Nations Environment Program (UNEP). September 2009
    Massive new report that goes beyond the usual IPCC report to make clear how the likely adverse effects of climate change are now thought to be much greater than even the IPCC reported. The section on "Management" contains a subsection on "Assisted Colonization" (p. 46 of the report; p. 4 of the PDF download), that includes these statements: "The reality of a rapidly changing climate has caught many natural-resource managers and policy-makers unprepared. Large-scale translocations might now be needed. Consequently, the conservation community needs to move beyond the preservation or restoration of species and ecosystems in place as the correct approach." and "Assisted colonization will always carry some risk, but these risks must be weighed against those of extinction and ecosystem loss. Already some regions of the Earth such as the Arctic are experiencing high levels of warming. Many others will experience unprecedented heat within the next 100 years, as well as altered precipitation and ocean acidity. The future for many species and ecosystems is so bleak that assisted colonization might be their best chance. These management decisions will require careful thought and will need to be backed up by detailed scientific understanding if they are to succeed."

  • "Science Journal Podcast" AAAS transcript. 24 September 2009
    One of the topics covered is the scientific controversy over the pros and cons of assisted migration. The work of citizen group Torreya Guardians is mentioned. (In PDF, so do internal Find search for "assisted migration".)

  • "Garden Plants Get a Head Start on Climate Change" by Sebastiaan Van der Veken et al, May 2008, Frontiers in Ecology and the Environment
    "We compared the natural ranges of 357 native European plant species with their commercial ranges, based on 246 plant nurseries throughout Europe. In 73% of native species, commercial northern range limits exceeded natural northern range limits, with a mean difference of ~ 1000 km. With migration rates of ~ 0.1 - 5 km per year required for geographic ranges to track climate change over the next century, we expect nurseries and gardens to provide a substantial head start on such migration for many native plants. While conservation biologists actively debate whether we should intentionally provide "assisted migration", it is clear that we have already done so for a large number of species." (excerpt from Abstract)

  • "Mapping California's Shifting Climate" KQED Climate Watch blog. 26 February 2010
    Cross-institutional report, with maps, on possible occurrence and velocity of climate change in California, along with response alternatives.

  • "Climate Change Turns Conservationists into Triage Doctors" CBC News (Canada). 30 November 2009
    Survey of a shift in conservationists attitudes: "The point is not to think outside the box, but to recognize that the box itself has moved and, in the 21st century, will continue to move more and more rapidly," University of Colorado ecologist Timothy Seastedt and his colleagues write in the journal Frontiers in Ecology and the Environment. Seastedt and others argue land managers must focus on ecosystem diversity to give plants and animals the best chance to adapt to the change scientists say is coming: The more diversified a system, the more resilient. Trying to return ecosystems to some historic or natural state is no longer possible, they say. "To be honest, the combination of climate and atmospheric chemistries we're experiencing now — you can't find any historical match," Seastedt says.

  • 2009 book highlights ASSISTED MIGRATION controversy, Heatstroke: Nature in an Age of Global Warming, by Anthony Barnosky (Island Press)
    Publisher's press release excerpt: Unfortunately, both assisted migration and Pleistocene rewilding would lead to managed ecosystems — the antithesis of wilderness. Just as we manage fisheries to preserve an important food source, we will have to give up some wildness in order to preserve species. "We can't protect all three faces of nature — ecosystem services, like clean water and fisheries; species diversity; and the feeling of wilderness — without somehow separating those three different concepts of nature and working with each one of them differently," [the author] says. "All can be complementary, but you have to do different things for each one. I think there are people who are quite happy to settle for one or two of those, but my personal philosophy and feeling is that we can have all three faces of nature." [The author] foresees two types of preserves, for example: species preserves to protect a species or assemblages of species, but requiring heavy management; and wildland preserves that retain ecological interactions without the influence of humans — the feel of wilderness — but which will see changing species and even extinctions.

  • "Hot Issue: Should We Deliberately Move Species?" Assoc. Press, 19 July 2009.
    Reports on the work of Greg O'Neill, a geneticist with the British Columbia Ministry of Forests and Range, who is already working with logging companies to replant logged forests in British Columbia not with the species that were logged, but with seeds of species currently native to much lower elevations or latitudes. [Same story also online at: http://www.cbsnews.com/stories/2009/07/20/tech/main5174392.shtml.]

  • "Butterflies Reeling from Impacts of Climate and Development" Proceedings National Academy of Sciences January 2010.
    Their most significant findings: 1. Butterfly diversity (the number of different species present) is falling fast at all the sites near sea level. It is declining more slowly or holding roughly constant in the mountains, except at tree line. 2. At tree line, butterfly diversity is actually going up, as lower-elevation species react to the warming climate by moving upslope to higher, cooler elevations. 3. Diversity among high-elevation butterflies is beginning to fall as temperatures become uncomfortably warm for them and, Shapiro says, "There is nowhere to go except heaven."

  • "Some California Amphibians May Need a Lift to Survive Climate Change" Scientific American online, by Brendan Borrell, 7 August 2009.
    "As temperatures rise over the next century, three California amphibian species could be pushed to the cusp of extinction because the warming climate will effectively block their migration to more suitable habitats. Interventions by humans who physically relocate the animals may be the only way to help them survive. . . The Torreya Guardians, a self-organized group of naturalists, botanists, ecologists and others, are the most well-known proponents of assisted migration. Last July, the group planted endangered Torreya taxifolia seedlings in new habitat patches north of their customary domain in Florida, where it is becoming too hot for the conifers to survive." (and more)

  • "Are Butterflies the Silent Harbinger of Global Warming?" report by journalist Seth Shulman, Grist, 17 June 2010.
    Excellent summary of Camille Parmesan's early and continuing leadership in pointing out the shift poleward and upslope in native range of butterfly and other species, including her landmark 1996 and 2003 papers in the journal Nature. Parmesan is the lead scientist on the United Nation's Intergovernmental Panel on Climate Change (IPCC).

  • "Driving Mr. Lynx" Ideas page article by journalist Chris Berdik, Boston Globe, 12 October 2008.
    Lengthy news article that surveys the assisted migration debate, from its roots in a 2004 article in Wild Earth journal to citizen-activism, scientific backlash, and the beginnings of a worldview shift. The work of Torreya Guardians is highlighted, along with the August 2008 official filing, under the Endangered Species Act, of a request (by scientist Camille Parmesan) to undertake the first intentional movement of an animal species (an endangered butterfly) in response to shifting climate.

  • "Rules of the Wild", sidebar to above article in Boston Globe, 12 October 2008.

  • "Moving on Assisted Migration" news report by Emma Marris, Nature, online 28 August 2008.
    One of the top journals in science reports on the article (immediately below) that had been published in the other top science journal, plus coverage of the special session on assisted migration at the Ecological Society of America meeting in August 2008. Torreya Guardians is presented as taking the action lead in pressing for a rethinking of how biodiversity is best protected.

  • POLICY FORUM: ECOLOGY: "Assisted Colonization and Rapid Climate Change" by O. Hoegh-Guldberg, L. Hughes, S. McIntyre, D. B. Lindenmayer, C. Parmesan, H. P. Possingham, and C. D. Thomas, in Science 18 July 2008: 345-346. PDF of original article
    This 2-page article in America's top science journal has spurred enormous coverage and debate over the topic of what was once known as "assisted migration". Click here for news reports of the article:

  • Earth News online (posts full report of journalist Lauren Morello, who interviewed Connie Barlow of Torreya Guardians to demonstrate the citizen-action side of the issue)
  • climateshifts.org (a spin-off report that mentions the work of Torreya Guardians)
  • Scientific American online (a spin-off report that mentions Torreya Guardians)
  • in Wired News
  • Wired Magazine commentary by Brandon Keim
  • CNN.com
  • Science Daily (online)
  • Official website "Managed Relocation" posted by the "Working Group" that formed at the Ecological Society of America meeting, August 2008.
    Content: Right now this is just a skeleton website, as the group goes about its work. But after it achieves a product, estimated for autumn 2009, this will be a key site to watch. Right now, you can find a list of group leaders and members on that site. Check out their LIST OF PUBLICATIONS AND MEDIA REPORTS on this topic.

  • University of Queensland interview with first author of the Science forum above.
    Hoegh-Guldberg says, "If we are to take the latest climate science seriously, then our current conservation strategies will not work for the majority of the species. To be blunt, they need to change. Even under the mildest rates of climate change, the habitat of many species will contract. Consequently, the future for many species and ecosystems is so bleak that assisted colonisation might be their only chance of survival."

  • "Can Assisted Migration Save Species from Global Warming?" Scientific American, March 2009
    A lengthy article featuring Camille Parmesan, first advocate for assisted migration among professional conservation biologists. Lots of excellent details on butterflies and other species threatened by climate change. Mentions work of Torreya Guardians in assisting Torreya taxifolia tree seedlings to venture northward in July 2008.

  • U.S. Fish & Wildlife Service "Internal Discussion Draft: Rising to the Urgent Challenges of a Changing Climate: Strategic Plan for Responding to Accelerating Climate Change in the 21st Century". Draft of 12 December 2008.
    "We will review, identify, and work to revise all elements of the Service's legal, policy, and regulatory framework necessary to support effective adaptive responses to changing climate. We will place particular focus on developing necessary new policies (e.g., assisted colonization) and needed revision of existing policies (e.g., what constitutes native, invasive, or exotic species?)." p. 15 "Novel conservation and recovery actions, such as assisted colonization, will be developed and implemented to protect acutely climate-vulnerable species." (p. 16)

  • "Assisted colonization is not a viable conservation strategy"(preprint of 2009 Trends in Ecology and Evolution paper) by Anthony Ricciardi and Daniel Simberloff
    Strong argument against assisted migration in top ecological journal. Excerpt: "Until we develop more accurate and general methods of predicting the impact of introduced species, cost-benefit analyses will be dangerously misleading. It is not yet possible to quantify the probability that a given species will go extinct because of climate change, or that a translocated species will harm one or more native species in a recipient community. To compare two such illusory numbers would lead to a false sense of scientific certainty. . . . Given this lack of predictive power, assisted colonization is tantamount to ecological roulette and should probably be rejected as a sound conservation strategy by the precautionary principle."

    Note: A letter to TEE journal commenting on the above is "Assisted colonization is a techno-fix" by Ioan Fazey and Joern Fischer.

  • "Why Saving a Species is a Mathematical Matter", 26 July 2011 news article online in Brisbane Times.
    Interview with lead author, Eve McDonald-Madden, of July 2011 paper in Nature Climate Change, "Optimal timing for managed relocation of species faced with climate change", with example of Australia's Golden Bowerbird. See also article in Live Science.

  • "Should Species Be Relocated to Prevent Extinction", by Devin Powell, Inside Science News Service, 24 August 2009
    EXCERPT: The most recognized assisted migration project to date may be the Torreya Guardians. This network of conservationists, which includes botanists and ecologists, is trying to save the Torreya taxifolia, an endangered evergreen that grows to 60 feet in height. The group has transplanted dozens of trees from the Florida panhandle, where it is rapidly disappearing, to sites in North Carolina that are thought to have a suitable climate. "Plants are so much easier to replicate than pandas," said Rob Nicholson of the Botanic Garden at Smith College in Northampton, MA. "Torreya roots easily ... and you could start knocking them out by the tens of thousands if you wanted to."

  • Science Writer Carl Zimmer surveys the assisted migration controversy, as of 6 May 2006 in "As climate warms, species may need to migrate or perish", published online in ONLINE OPINION: Australia's e-journal of social and political debate.
    Zimmer's survey includes the context of the Ricciardi and Simberloff paper (directly above), and Jessica Hellman's comment on that paper, where she says, "Is the alternative just to forsake a species?" she asks. "I just don't want to sit back and say, 'Oh the world is going to hell'."

  • "Bugs: The Forgotten Victims of Climate Change", 3 July 2009 news article online in Live Science.
    Surveys managed relocations controversy as it pertains to insects; mention of need to assess insect tolerance of climate change in all their life stages; quotes Jessica Hellman.

  • "Big Plans for a Little Butterfly", 6 July 2009 news article online Mercury News.
    Project proposed to re-introduce extinct populations of Bay Checkerspot at the famous site where Paul Ehrlich and students studied them for 5 decades: "'We may end up having to try to readjust natural communities all over the planet,' Ehrlich warned. 'Reintroduction is a dice game,' said Carol Boggs, a Stanford biologist who would direct the experiment. 'What we'd like to understand is how to load the dice in our favor. And this is the perfect place to try it.' Researchers will spend the next year designing the experiment, which must be approved by both Stanford officials and the U.S. Fish and Wildlife Service. Stanford spokesman Larry Horton cautions that the university has not yet taken a position. The U.S. Fish and Wildlife Service, which protects endangered species, said it would support the effort, if done correctly. The Stanford scientists would use contrasting strategies — perhaps introducing insects at different phases in the life cycle, into different plots, at different seasons, Boggs said. Mowing, grazing or other human interventions would be needed to sustain it. By managing the introduction, Stanford scientists would build, in essence, a butterfly lab."

  • "University of Otago Rock Wren Project", 6 July 2009 online New Zealand abstract of new research project.
    Project abstract discusses methods to help ailing New Zealand bird, including assessment of assisted migration.

  • "Assisted Colonization: CBC Radio Interview"
    A terrific AUDIO exploration of the controversy, which aired 24 July 2008. Part 1 is the supportive side, via an interview with Prof. Camille Parmesan. Part 2 is an interview with an invasive species researcher that is very critical of the idea. Part 3 is a not-to-be-missed radio spoof of the idea.

  • "Rewilding Torreya taxifolia to Waynesville, North Carolina, July 2008" Torreya Guardians webpage posted by Connie Barlow, August 2, 2008.
    A richly illustrated PHOTO-ESSAY, with links to a complete chronology, of the REWILDING ACTION that Torreya Guardians undertook for 31 potted seedlings. A writer and a photographer commissioned by Audubon magazine documented the action (which will probably be published in a summer 2009 issue of Audubon.

  • "Terrestrial Orchid Conservation in the Age of Extinction", Annals of Botany 2009 104(3):543-556.
    Excerpt: "Assisted translocation/migration represent new challenges in the face of climate change; species, particularly orchids, will need artificial assistance to migrate from hostile environments, across ecological barriers (alienated lands such as farmlands and built infrastructure) to new climatically buffered sites. It is likely that orchids, more than any other plant family, will be in the front-line of species to suffer large-scale extinction events as a result of climate change."
        See also an online biogeographic article that reports on the existing use of assisted migration for Australian orchids.

  • "Orchids Flourish with Assisted Migration", Yale Environment Review (of June 2012 paper in Biological Conservation by Hon Liu et al).
    Excerpt: A recent study in Biological Conservation announced success with the migration of one of the world’s most beloved and charismatic plants: orchids. Chinese researchers examined the effects of assisted migration during a massive orchid rescue effort in 2006 that relocated 1000 endangered plants of 29 rare and endangered species from a lowland area that would be flooded by a hydropower project in the Longtan reservoir in Guangxi, southwestern China. Individual plants were moved 30 kilometers southeast to an altitude of 1000 meters above sea level, 600 meters higher than their original setting. Researchers labeled and mapped 462 individual plants from 20 species and tracked their flowering and survival six times over a 5-year period following the migration. The relocation area was situated outside the native elevation range of 70 percent of the species, offering the opportunity to compare responses between individuals within and outside of their native range. The researchers found that nearly all orchids were remarkably resistant to the climatic and grazing pressures, and that all species flowered in the new conditions.

  • "Species on the Move" June 8, 2009 May 28, 2009 ABC Science (online) report by Dani Cooper
    Lots of excellent details on the AUSTRALIAN species for whom assisted migration is being assessed, plus scientists quoted pro and con.

  • "Climate Change and Translocations: The Potential to Re-establish Two Regionally Extinct Butterfly Species in Britain", Biological Conservation, Matthew J. Carroll et al.
    ABSTRACT: Climate change is causing many organisms to migrate to track climatically-suitable habitat. In many cases, this will happen naturally, but in others, human intervention may be necessary in the form of "assisted colonisation." Species re-establishments in suitable parts of their historic ranges provide an opportunity to conserve some species and to test ideas about assisted colonisation. Here, bioclimatic models of the distributions of two extinct British butterflies, Aporia crataegi and Polyommatus semiargus, were used to investigate the potential for re-establishment in Britain. . .

  • "Assisted Colonization Key to Species' Survival in Changing Climate" Feb 19, 2009 Innovations Report.
    Detailed news report of "the first successful test case of assisted colonization". In 1999 and 2000, scientists introduced populations of two species of butterfly miles north of their then-current range in England. A just-published paper reports the results:
    Source: Willis, S.G. et al. 2009. Assisted colonization in a changing climate: a test-study using two U.K. butterflies. Conservation Letters DOI: 10.1111/j.1755-263X.2008.00043.x. Their abstracts concludes, "We suggest that assisted colonization may be a feasible and cost-effective means of enabling certain species to track climatic change."

  • "Assisted Migration" chapter of 2007 PhD thesis by the scientist who coined the term: Brian Keel.
    The full title of Keel's thesis is "Assisted Migration as a Conservation Strategy for Rapid Climate Change: Investigating Extended Photoperiod and Mycobiont Distributions for Habenaria repens Nuttall (Orchidaceae) as a Case Study". The link above connects to a PDF of his chapter 3. Note: His PhD thesis abstract is available online and in book format: Assisted Migration as a Conservation Strategy for Rapid Climate Change: Investigating Extended Photoperiod and Mycobiont Distributions of Habenaria Repens Nuttall (Orchidaceae) as a Case Study. Keel is also coauthor of a chapter on Managed Relocation in a 2012 edited volume, Plant Reintroduction in a Changing Climate: Promises and Perils.

  • "Defining Migration" chapter of the Brian Keel thesis, above.
    This short chapter will be useful for those engaged in considering whether "assisted migration" or "assisted colonization" is the best term for the kinds of conservation actions now beginning to be considered.

  • "Assisted Migration or Assisted Colonization: What's in a Name?" commentary posted on Torreya Guardians website.
    Torreya Guardians (and others) are invited to post comments on whether the original term, "assisted migration," should be replaced with the term more recently proposed, "assisted colonization."

  • "Joshua Trees Nearly Wiped Out by 2100?" by Jessica Marshal, 25 March 2011, Discovery News.
    "Ken Cole of the U.S. Geological Survey in Flagstaff, Ariz., and an interdisciplinary group of colleagues used information about the current distribution of Joshua trees combined with climate models to predict where the trees may be by 2070 to 2099." Using Pleistocene evidence in extinct ground sloth dung, data on the lack of recent reproduction in Joshua Tree National Monument (California), this tall member of the Yucca plant type, becomes the "poster plant" for "assisted migration" in the American West. Joshua Tree National Monument was, as it turns out, created too close to the southern edge of the 20th-century range of Joshua Trees, and thus may be doomed to loss of its namesake plant. See also, "Joshua Trees Losing Ground, Fast".

  • "Ground Truthing" blog post by Chris Clarke, 17 January 2008
    Revisits a previous blog on the possible extinction of California's Joshua Tree, owing to an inability to disperse and thus track climate changes. In this blog, Clarke mentions the work of Torreya Guardians in assisting migration of a critically endangered tree in eastern North America.

  • "Outlook Bleak for Joshua Trees" NPR online article and "All Things Considered" audio, 4 February 2008
    Interview of scientists and managers working in Joshua Tree National Park; prospects for the extirpation of Joshua Trees in the park as climate changes; the role of extinct ground sloths in past seed dispersal of this tallest of all yuccas. Audio interview of a trip to a cave looking for sloth dung.

  • "When Worlds Collide" by Douglas Fox, Conservation Magazine, Jan-March 2007 (cover story).
    Subtitle: "Climate change will shuffle the deck of plants, animals, and ecosystems in ways we've only begun to imagine."
    Content: Surveys beginnings of debate about whether to actively assist species in shifting their geographic ranges. The work of Torreya Guardians is mentioned.

  • "A Framework for Debate of Assisted Migration in an Era of Climate Change" by Jason S. McLachlan, Jessica J. Hellman, and Mark W. Schwartz, Conservation Biology, April 2007, Vol 21: 297-302.
    Content: The paper begins, "The Torreya Guardians are trying to save the Florida torreya from extinction. . . The focus of Torreya Guardians is an 'assisted migration' program that would introduce seedlings to forests across the Southern Appalachians and Cumberland Plateau. Their intent is to avert extinction by deliberately expanding the range of this endangered plant over 500 km northward. . . If circumventing climate-driven extinction is a conservation priority, then assisted migration must be considered a management option. . . Assisted migration is a contentious issue that places different conservation objectives at odds with one another. This element of debate, together with the growing risk of biodiversity loss under climate change, means that now is the time for the conservation community to consider assisted migration. Our intent here is to highlight the problem caused by a lack of a scientifically based policy on assisted migration, suggest a spectrum of policy options, and outline a framework for moving toward a consensus on this emerging conservation dilemma."

  • "Assisted Migration: Helping Nature to Relocate" by Bob Holmes, New Scientist, 3 October 2007.
    Content: Superb and lengthy science reporting on the above paper that appeared in Conservation Biology, with much additional information, insights, and arguments culled from the authors and other scientists and conservation managers. Highlights issues related to speed of migration (past evidence as well as estimates of future needs) and regional changes in climate. An article referenced within the report by Jason McLachlan et al., is also important to read: "Molecular Indicators of Tree Migration Capacity Under Rapid Climate Change" in Ecology, 2005, Vol 86, pp. 2088-98.

  • "A Radical Step to Preserve Species: Assisted Migration" by Carl Zimmer, New York Times (Science Times), 23 January 2007 (lead story).
    Content: References a forthcoming paper to be published in the journal Conservation Biology that encourages debate on the topic, by Mark Schwartz, Jason McLachlan, and Jessica Hellman

  • "You-Tube video of Jessica Hellman on insect assisted migration", Notre Dame Research 3-minute documentary.
    Content: Great intro for popular audiences; shows lab experiments with insects in climate simulated settings.

  • "Don't Judge Species on Their Origins" comment by Mark Davis et al., Nature, 9 June 2011.
    Excerpt: "Today's management approaches must recognize that the natural systems of the past are changing forever thanks to drivers such as climate change, nitrogen eutrophication, increased urbanization and other land-use changes. It is time for scientists, land managers and policy-makers to ditch this preoccupation with the native v. non-native dichotomy and embrace more dynamic and pragmatic approaches to the conservation and management of species — approaches better suited to our fast-changing planet.

  • "U.S. Agrees to Consider Protection for Pikas" report by Jane Kay in San Francisco Chronicle, 13 February 2009.
    Endangered Species Act invoked by Center for Biological Diversity to protect pikas threatened by global warming in the alpine peaks home in mainland U.S. No mention yet of assisted migration for the subspecies of pika trapped on warming mountain tops.

  • "Threatened Species 'Need Help' Finding Cooler Homes" news report by Catherine Brahic New Scientist Environment (online), 18 July 2008.
    News report on the 18 July 2008 paper in Science by Hoegh-Guldberg et. al (above).

  • "What Another Century of Global Warming Could Do to Our Wilderness" by Bert Gildart in Wilderness Magazine, September 2008.
    Great overview of looming problems for ecosystems (such as the Everglades) and species (such as Mountain Pica), some of which are already happening. No mention of assisted migration, of course, as this degree of human intervention would be a very delicate issue for the "wildest" of landscapes, especially for formally designated wilderness areas.

  • "Plants at Thoreau's Walden Pond Affected by Climate Change in the Area", Assoc. Press News Story, 27 October 2008.
    A 4.3 degree F. area-specific rise in temperature over the past century has affected plants in this sacred spot of environmentalism in Massachusetts. Notably, the plants hardest hit are those that did not alter their spring flowering time in tandem with the shift in earlier seasonal warming.

  • "Pre-emptive Strike: Outwitting Extinction", by Emma Marris, Nature Reports Climate Change (Online) 23 October 2008.
    The IUCN has issued a report on "climate change susceptible" species. "Assisted migration" is mentioned as one of the possible management responses, as well as enlarged biological preserves and focussing on entire ecosystems, not merely individual species.

  • "On the Use of Taxon Substitutes in Rewilding Projects on Islands" by Dennis M. Hansen, 2010, chapter in Islands and Evolution, Perez-Mellado et. al, eds.
    Extract: "I hope the examples here, as well as the case studies, will illustrate the potential for taxon substiution to rapidly move beyond the status of gimmck and become an integral part of restoration schemes for some of the most degraded habitats on our planet."

  • "Ecological History and Latent Conservation Potential: Large and Giant Tortoises as a Model for Taxon Substitutions" by Dennis M. Hansen et al. Ecography: 33: 272-84 (2010)
    ABSTRACT: Starting in the late 1970s, ecologists began unraveling the role of recently extinct large vertebrates in evolutionary ecology and ecosystem dynamics. Three decades later, practitioners are now considering the role of ecological history in conservation practice, and some have called for restoring missing ecological functions and evolutionary potential using taxon substitutes  extant, functionally similar taxa  to replace extinct species. This pro-active approach to biodiversity conservation has proved controversial. Yet, rewilding with taxon substitutes, or ecological analogues, is now being integrated into conservation and restoration programmes around the world. Empirical evidence is emerging that illustrates how taxon substitutions can restore missing ecological functions and evolutionary potential. However, a major roadblock to a broader evaluation and application of taxon substitution is the lack of practical guidelines within which they should be conducted. While the International Union for Conservation of Nature’s reintroduction guidelines are an obvious choice, they are unsuitable in their current form. We recommend necessary amendments to these guidelines to explicitly address taxon substitutions. A second impediment to empirical evaluations of rewilding with taxon substitutions is the sheer scale of some proposed projects; the majority involves large mammals over large areas. We present and discuss evidence that large and giant tortoises (family Testudinidae) are a useful model to rapidly provide empirical assessments of the use of taxon substitutes on a comparatively smaller scale. Worldwide, at least 36 species of large and giant tortoises went extinct since the late Pleistocene, leaving 32 extant species. We examine the latent conservation potential, benefits, and risks of using tortoise taxon substitutes as a strategy for restoring dysfunctional ecosystems. We highlight how, especially on islands, conservation practitioners are starting to employ extant large tortoises in ecosystems to replace extinct tortoises that once played keystone roles.

  • "Bolson Tortoises of the Pleistocene assisted to move north to New Mexico" New Mexico Wilderness Alliance, Rewilding Institute Website, January 2008.
    Content: 37 Bolson Tortoises (larger than a desert tortoise) were moved from a private ranch in Arizona to protected lands in New Mexico where they are being bred and managed expressly for "rewilding" into their former habitat.

  • "Beyond Historic Baselines: Restoring Bolson Tortoises to Pleistocene Range", by Joe Truett and Mike Phillips, in Ecological Restoration, June 2009, pp 144-151.
    Abstract: Ecological restoration in North America traditionally has strived to return ecosystems to some semblance of the early historic (post-Columbian) condition. Emerging alternative paradigms recognize the large impacts exerted by pre-Columbian peoples, the ever-changing nature of ecosystems regardless of anthropogenic effects, and the possibility of using other benchmarks. Recently, the Turner Endangered Species Fund initiated a project to restore the endangered bolson tortoise to an area in southern New Mexico within its late Pleistocene, but not historic range. Justifications included the likelihood that prehistoric humans extirpated it from New Mexico, the presence of habitats similar to those in its current range in Mexico, and escalating threats to species there. . . Restoring imperiled species to prehistoric ranges has some precedent in North America and, we believe, merits increasing consideration as historic ranges of some species offer increasingly less security.

  • "Mauritius: Back to Wildlife [Tortoises]" article in The Guardian Weekly Online, 22 September 2008.
    Content: Aldabran Giant Tortoises used as proxies for the Mauritius giant tortoises that had been exterminated. "Rewilding" a small island near Mauritius with these giant tortoises.

  • "Coevolution of Cycads and Dinosaurs" paper by George E. Mustoe, The Cycad newsletter, March 2007.
    Barlow and Martin 2004 proposed that Torreya taxifolia might have gotten trapped in its peak-glacial pocket reserve (in northern Florida) for lack of its coevolved seed disperser, and thus was unable to geographically respond to the warming interglacial climate. The above paper suggests that another taxon of gymnosperm that thrived (along with genus Torreya) in the Jurassic period might have suffered from an inability to easily track climate change when the seed-dispersing dinosaurs died out.



       Download in PDF two CLASSIC ARTICLES, for and against assisted
       migration of Torreya taxifolia, published as the featured
       Forum in the Winter 2005 issue of Wild Earth. Download
       the pro and con articles separately for printing on standard   
       size paper. Or, for viewing the 2-article Forum as it
       appeared in publication (wide-screen, with all illustrations),
       download the "Forum."
       


      FOR assisted migration, by Connie Barlow & Paul Martin  
     

      ANTI assisted migration by Mark Schwartz
     

      FORUM (both articles for wide screen)
     

  • "Biologists Debate Relocating Imperiled Species" by Philip Bethge Spiegel Online International (English edition) 23 November 2007.
    Content: News report on how climate change will threaten animal and plant species; includes coverage of Torreya taxifolia and mentions Torreya Guardians.

  • Discussion on a Blog Devoted to Snails and Slugs editorial, December 2008.
    Content: Blogs and comments debate "assisted migration/colonization" with respect to snails; includes some case history of attempt to relocated endangered snails from New Zealand mainland to an island off NZ.

  • "Some Endangered Species May Be Shifted to More Congenial Habitats" editorial, in The Times of India 3 February 2007.
    Content: Editorial in favor of assisted migration for endangered species.

  • "Climate Change and Assisted Migration of At-Risk Orchids" by Brian G. Keel, p. 9 of Orchid Conservation News (Woodland, CA), March 2005.
    Content: Advocacy and statement of conditions that merit assisted migration intervention for orchids

  • "Climate Change and Moving Species: Furthering the Debate on Assisted Colonization" by Malcolm L. Hunter, 2007, Conservation Biology Vol 21: 1356-58.
    Content: Makes case for using the term "assisted colonization" rather than "assisted migration"; proposes three features for testing advisability of any particular species for such intervention: (1) their probability of extinction due to climate change, (2) their vagility, (3) and their ecological roles.

  • "Climate Change Impacts and Adaptation: A Canadian Perspective" Natural Resources of Canada.
    Content: Governmental publication in favor of assisted migration of tree species in anticipation of climate change.

  • "A Landscape in Transit" by Betsy Mason, Contra Costa Times (Woodland, CA), 24 January 2007.
    Content: Effect of global warming on California blue oaks and other trees.

  • "Assisted Colonisation" blog by Andrew Guerin, 18 July 2007.
    Content: Marine biologist highly skeptical of the merits of considering assisted colonisation for marine species.

  • "Macquarie Biologist's Grave Warning on Species Survival", news report.
    Content: Professor Lesley Hughes, co-author of the 18 July 2008 paper in the journal Science (O. Hoegh-Guldberg et. al), is interviewed by the web news of her university. Also click on an AUDIO INTERVIEW with Professor Hughes (scroll down to 30 June 2008, "Climate Change Peril").



    Pleistocene Rewilding and Taxon Substitution for Ecological Restoration

         Paul S. Martin originated the concept of Pleistocene Rewilding and Taxon Substitution in the 1970s. You can learn more about his early work in that field by accessing this page: Tribute to Paul S. Martin.

    The VIDEO at left is an illustrated version of a 1996 phone interview Connie Barlow did with Paul specifically about his "Pleistocene Rewilding" concept.

  • "Is the Climate Right for Pleistocene Rewilding? Using Species Distribution Models to Extrapolate Climatic Suitability for Mammals across Continents", by Orien MW Richmond et al., PLoS One 5(9): e12899. doi:10.1371/journal.pone.0012899
    ABSTRACT begins: Species distribution models (SDMs) are increasingly used for extrapolation, or predicting suitable regions for species under new geographic or temporal scenarios. However, SDM predictions may be prone to errors if species are not at equilibrium with climatic conditions in the current range and if training samples are not representative. Here the controversial "Pleistocene rewilding" proposal was used as a novel example to address some of the challenges of extrapolating modeled species-climate relationships outside of current ranges. Climatic suitability for three proposed proxy species (Asian elephant, African cheetah and African lion) was extrapolated to the American southwest and Great Plains using Maxent, a machinelearning species distribution model.

  • "Rewilding North America" by Josh Donlan and 11 other authors, Nature, 18 August 2005 (2 pages).
    Content: The first advocacy article ("commentary") by prominent conservation biologists that proposes "rewilding" close-kin of some of the large mammals that went extinct in North America at the end of the Pleistocene, 13 thousand years ago by reintroducing close relatives or proxies.

  • "Pleistocene Rewilding: An Optimistic Agenda for the 21st Century" by Josh Donlan and 11 other authors, American Naturalist, November 2006, vol 168: pp 660-681.
    Content: This is the long and fully developed version of the 2005 paper, by the same set of authors. Abstract: Large vertebrates are strong interactors in food webs, yet they were lost from most ecosystems after the dispersal of modern humans from Africa and Eurasia. We call for restoration of missing ecological functions and evolutionary potential of lost North American megafauna using extant conspecifics and related taxa. We refer to this restoration as Pleistocene rewilding; it is conceived as carefully managed ecosystem manipulations whereby costs and benefits are objectively addressed on a case-by-case and locality-by-locality basis. Pleistocene rewilding would deliberately promote large, long-lived species over pest and weed assemblages, facilitate the persistence and ecological effectiveness of megafauna on a global scale, and broaden the underlying premise of conservation from managing extinction to encompass restoring ecological and evolutionary processes. Pleis tocene rewilding can begin immediately with species such as Bolson tortoises and feral horses and continue through the coming decades with elephants and Holarctic lions. Our exemplar taxa would con- tribute biological, economic, and cultural benefits to North America. Owners of large tracts of private land in the central and western United States could be the first to implement this restoration. Risks of Pleistocene rewilding include the possibility of altered disease ecol- ogy and associated human health implications, as well as unexpected ecological and sociopolitical consequences of reintroductions. Estab- lishment of programs to monitor suites of species interactions and their consequences for biodiversity and ecosystem health will be a significant challenge. Secure fencing would be a major economic cost, and social challenges will include acceptance of predation as an over- riding natural process and the incorporation of pre-Columbian eco- logical frameworks into conservation strategies.

  • "Pleistocene Rewilding" New York Times Magazine article by Alan Burdick, 12/11/05.
    Content: Summary of one of the NYT's pick-of-the-year best ideas.

  • "Pleistocene Dreams" Orion Magazine, Point of View editorial by Josh Donlan, July 2008.
    A biophilia, soul-centered, and future-generational plea for beginning the bold task of megafaunal Pleistocene Rewilding.

  • "Rewilding Megafauna: Lion and Camels in North America?" an interview with Connie Barlow, by actionbioscience.org, March 2007.
    Content: Lengthy interview with Connie Barlow discussing the Pleistocene megafaunal rewilding concept. Very useful links to other related articles and audios at the end.

  • Transcript of 11/20/09 Science podcast on on the concurrent paper in the journal, "Pleistocene Megafaunal Collapse, Novel Plant Communities, and Enhanced Fire Regimes in North America" by Jackquelyn L. Gill et al.
    ABSTRACT of paper: Although the North American megafaunal extinctions and the formation of novel plant communities are well-known features of the last deglaciation, the causal relationships between these phenomena are unclear. Using the dung fungus Sporormiella and other paleoecological proxies from Appleman Lake, Indiana, and several New York sites, we established that the megafaunal decline closely preceded enhanced fire regimes and the development of plant communities that have no modern analogs. The loss of keystone megaherbivores may thus have altered ecosystem structure and function by the release of palatable hardwoods from herbivory pressure and by fuel accumulation. Megafaunal populations collapsed from 14,800 to 13,700 years ago, well before the final extinctions and during the B√łlling-Aller√łd warm period. Human impacts remain plausible, but the decline predates Younger Dryas cooling and the extraterrestrial impact event proposed to have occurred 12,900 years ago.

  • "Resolving lost herbivore community structure using coprolites of four sympatric moa species" by J.R. Wood et al. in PNAS, Aug 2013.
    ABSTRACT EXCERPT: Knowledge of extinct herbivore community structuring is essential for assessing the wider ecological impacts of Quaternary extinctions and determining appropriate taxon substitutes for rewilding. Here, we demonstrate the potential for coprolite studies to progress beyond single-species diet reconstructions to resolving community-level detail. . . Our results show that moa lack extant ecological analogs, and their extinction represents an irreplaceable loss of function from New Zealand's terrestrial ecosystems.

  • "Pleistocene Dreams" by J. C. Hallman in Seach Magazine, May/June 2008.
    Content: Lengthy report on the author's visits to talk with some of the leaders in Pleistocene Rewilding movement.

  • "Pleistocene Park: Where the Auroxen Roam" by Andrew Curry. 2008. Wired Magazine 16.10
    Content: A long report of the rewilding of Europe's endangered native bison to a 500 acre preserve in Latvia that will also contain other surrogates for Pleistocene megafauna.

  • "Conservation Biology: Reflecting the Past" by Emma Marris, Nature 462, 30-32 (2009)
    Tag line: Unsatisfied with merely halting environmental destruction, some conservationists are trying to reconstruct ecosystems of the past. Emma Marris travels back in time with the rewilders.

  • "Role of Ecological History in Invasive Species Management and Conservation by C. Josh Donlan and Paul S. Martin, Conservation Biology, 1 February 2004
    Conclusion: "Nativeness, place, and history are central to the science, strategies, and aesthetics of biodiversity. Currently, a post-Columbian bias blinds us from a paleoecological view of North America, a vista with widespread policy implications. The attention of the public, long enchanted with dinosaurs, needs to shift to our indigenous Pleistocene patrimony. We lost and cannot replace the Ornithischia. We can resurrect and along the way help save the Proboscidea."

  • "Resurrecting Extinct Interactions with Extant Substitutes" by Christine J. Griffiths et al., Current Biology 21(8), April 26, 2011
    Summary: Rewilding with taxon substitutes, the intentional introduction of exotic species to replace the ecosystem functions of recently extinct species, is one way to reverse ecosystem dysfunction following the loss of species interactions [2]. This is highly controversial [3], in part because of a lack of rigorous scientific studies [4]. Here we present the first empirical evidence of an in situ rewilding project undertaken as a hypothesis-driven ecosystem management option. On Ile aux Aigrettes, a 25-hectare island off Mauritius, the critically endangered large-fruited endemic ebony, Diospyros egrettarum (Ebenaceae), was seed-dispersal limited after the extinction of all native large-bodied frugivores, including giant tortoises. We introduced exotic Aldabra giant tortoises, Aldabrachelys gigantea, to disperse the ebony seeds. Not only did the tortoises ingest the large fruits and disperse substantial numbers of ebony seeds, but tortoise gut passage also improved seed germination, leading to the widespread, successful establishment of new ebony seedlings. Our results demonstrate that the introduction of these exotic frugivores is aiding the recovery of ebonies. We argue for more reversible rewilding experiments to investigate whether extinct species interactions can be restored.
       See also: authors' press release; BBC News Online; Mail Online (UK); Discovery News.

  • "On the Use of Taxon Substitutes in Rewilding Projects on Islands" by Dennis M. Hansen, Islands and Evolution, 2010, 33 pages in PDF.
    In-depth survey of the most advanced on-the-ground example of "rewilding" that has occurred to date, written by one of the principal scientists leading the effort. Hansen writes, "I believe islands offer some of the best-suited scenarios to rapidly advance our empirical understanding of rewilding and exploring the use of taxon substitutions in conservation and restoration."

  • "The Use of Extant Non-Indigenous Tortoises as a Restoration Tool to Replace Extinct Ecosystem Engineers" by Christine J Griffiths et al, Restoration Ecology, 2010.
    Content: We argue that the introduction of non-native extant tortoises as ecological replacements for extinct giant tortoises is a realistic restoration management scheme, which is easy to implement. We discuss how the recent extinctions of endemic giant Cylindraspis tortoises on the Mascarene Islands have left a legacy of ecosystem dysfunction threatening the remnants of native biota, focusing on the island of Mauritius because this is where most has been inferred about plant-tortoise interactions. There is a pressing need to restore and preserve several Mauritian habitats and plant communities that suffer from ecosystem dysfunction.

  • "Rodrigues Island: Hope thrives at the Franćois Leguat Giant Tortoise and Cave Reserve" by David A. Burney, Madagascar Conservation and Development, June 2011.
    2-pages illustrated review of a tortoise restoration project on the island of Rodgrigues, and how the tortoises are helping to restore highly endangered native plants.

  • "Conservation and restoration of plant-animal mutualisms on oceanic islands" by Christopher N. Kaiser-Bunbury et al, Perspectives in Plant Ecology, Evolution and Systematics, 2010.
    13 pages, with color illustrations, on island restoration and rewilding efforts focusing on using congenerics or other species proxies where extinctions preclude restoring historically native species with whom extant native plants coevolved.

  • "Seed Dispersal and Establishment of Endangered Plants" on Oceanic Islands and the Use of Ecological Analogues", www.PLOSone, by Dennis M. Hanson et. al, May 2008.
    Content: Meshes "ecological anachronisms," conservation biology, rewilding of ecological proxies/analogs, and assisted migration/colonization, in a landmark paper that experimentally demonstrates the ecological viability and conservation value of introducing Aldabran tortoises to the oceanic island of Mauritius as ecological proxies (seed-dispersal agents) for Mauritian tortoises that were driven into extinction by humans.

  • "Rewilding Megafauna: Lions and Camels in North America?" interview with Connie Barlow, March 2007.
    Content: in-depth interview on Pleistocene Rewilding: its conservation potential and ethical and ecological justifications.

  • "Rewilding America, Pleistocene Style" The Monitor's View, Christian Science Monitor, 30 August 2005.
    Content: Editorial generally supportive of the August 2005 paper in Nature.

  • "Should Humans Give 'Hot' Animals a Hand?" by staff, Daily Democrat (Woodland, CA), 24 January 2007.
    Content: Lots of quotes from Dr. Mark Schwartz on the assisted migration issue.

  • "Restoring America's Big, Wild Animals" by Josh Donlan, Scientific American, June 2007.
    Lead author of the "Pleistocene Rewilding" paper originally published in Nature writes for a popular audience and responds to criticism that has emerged.

  • "Bring Elephants to Australia?" by David Bowman, Nature, 2 February 2012.
    Proposes introducing elephants and bringing back a proxy (Komodo dragon) for a giant extinct lizard in an effort to control rampant wildfires energized by alien grasses and alien predators of native marsupials. For excellent commentary and background on this paper, see: Australia's Newest Firefighters: Elephants?" by Nidhi Subbaraman.

  • "Big Animal Extinction 'severed nutrient arteries'" by Mark Kinver, BBC News, 12 August 2013.
    "The demise of big animals in the Amazon region 12,000 years ago cut a key way that nutrients were distributed across the landscape, a study has suggested. Researchers say animals such as huge armadillo-like creatures would have distributed vital nutrients for plants via their dung and bodies."

  • "Bringing Back Europe's Prehistoric Beasts" by Jens-Christian Svenning, Scientific American.com, June 2007.
    Proposes rewilding the endangered Asiatic lion into Europe.

  • "Pleistocene Rewilding" webpages
    Ongoing reports, news articles, and blog entries on this topic, posted at the The Rewilding Institute website.

  • "Pleistocene Rewilding" WIKIPEDIA entry
    Wikipedia entry, with photos and references, on this topic.

  • "The North Atlantic Ocean: Need for Proactive Management", by John C. Briggs. Fisheries, April 2008. Vol 33, pp. 180-184.
    For those of us considering the importance of "assisted migration" of species impacted by climate change, or outright "rewilding" of species or surrogates to regions in which they lived thousands of years ago, this paper is something to ponder. Here the author proposes that the collapses of fisheries in the North Atlantic may be irreversible without infusion of new species diversity, and that much is to be gained (and little risked) by introducing North Pacific fishes into the North Atlantic. The deep-time discussion of "The Great Trans-Arctic [Marine] Biotic Interchange" (which began 3.5 million years ago when the Bering Land Bridge was transgressed by marine waters), is crucial reading for those of us working with entirely terrestrial biotas.

  • "Rewilding Megafauna: Lions and Camels in North America?" Interview with Connie Barlow
    Interview published on the Action Bioscience website, an education resource of the American Institute of Biological Science

  • "Cloning Mammoths for Pleistocene Rewilding" blogpost
    Useful blogpost and comments on the possibility of cloning frozen mammoth DNA from flesh or sperm.

  • "Michael Archer: How we'll resurrect the gastric brooding frog, the Tasmanian Tiger"
    17-minute video from the TEDx "De-Extinction" series of talks, 2013.

  • "George Monbiot: For more wonder, rewild the world"
    15-minute video from TEDx, featuring the ecological benefits of bringing wolves back to Yellowstone, and advocacy for bringing back the extinct megafauna and how plants alive today in Europe seem adapted to elephants and rhinoceros. "Rewilding offers us the hope that our silent spring could be replaced by a raucous summer." And from an online essay: "Understorey trees such as holly, box and yew have much tougher roots and branches than canopy trees, despite carrying less weight. Our trees, in other words, bear strong signs of adaptation to elephants. Blackthorn, which possesses very long spines, seems over-engineered to deter browsing by deer; but not, perhaps, rhinoceros."

  • "Doom of the elephant-dependent trees in a Congo tropical forest"
    2013 paper by David Beaune et al, published in Forest Ecology and Management. On how extirpation of forest elephants in the Congo is diminishing or eliminating seed dispersal of forest trees have fruits that evidence the "megafaunal dispersal syndrome."


    Click here for Proposed Standards for Assisted Migration of Plants.

    Visit The Rewilding Institute.


     

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