Assisted Migration and Rewilding
of Plants and Animals
In an Era of Global WarmingLinks to Journal and Magazine Articles
"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.
"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."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."
"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
Download in PDF two 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.
"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.
"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.
"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.
"Brave Old World: The Debate Over Rewilding North America with Ancient Animals" by Eric Jaffe, Science News, 11 November 2006.Content: News report on the American Naturalist paper cited above.http://www.csmonitor.com/2005/0830/p08s02-comv.html
"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.
"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.
Click here for Proposed Standards for Assisted Migration of Plants.
Visit The Rewilding Institute.