Literaturdatenbank
Literaturdatenbank |
|
 |
|
Traphagen, M. B., & Kiester, A. R. , Restoration of the bolson tortoise (gopherus flavomarginatus) in north america. Paper presented at Turtle Survival Alliance 2007 Annual Meeting.
Added by: Sarina Wunderlich (01 Jan 2009 23:10:47 UTC) |
| Resource type: Proceedings Article BibTeX citation key: Traphagen2007 View all bibliographic details  |
Categories: General Keywords: Gopherus, Gopherus flavomarginatus, Habitat = habitat, Nordamerika = North America, Schildkröten = turtles + tortoises, Testudinidae Creators: Kiester, Traphagen Collection: Turtle Survival Alliance 2007 Annual Meeting |
Views: 4/586
Views index: 10% Popularity index: 2.5% |
| Abstract |
|
The Bolson Tortoise (Gopherus flavomarginatus) is an outstanding candidate for reintroduction into its former late Pleistocene range. Currently, the species occurs exclusively in a remote region of northern Mexico known as the Bolson de Mapimi located at the southern margin of the Chihuahuan desert. The tortoise enjoyed a much larger distribution until the close of the Pleistocene, occurring throughout much of Arizona, New Mexico and Texas. The mechanisms for extirpation from its former range are not well understood, a trait shared with much of the extinct Pleistocene mega-fauna. The Bolson tortoise is unique in that it is a survivor of the Pleistocene extinction event, providing an opportunity to study the mechanisms responsible for those extinctions, i.e. climate and “overkill.” In the last century the range and population of the tortoise has been further reduced and fragmented due to direct human impact in the form of over-collecting for food and the pet trade. The incursion of roads, railways and agriculture has also negatively affected the species, and it is likely that fewer than 10,000 tortoises currently remain in the wild. Preparing for restoration (“rewilding” in the parlance of mega-fauna reintroduction) involves: 1) understanding the tortoise’s ecology in its current, highly restricted range in the Bolson de Mapimi; 2) developing a significant captive breeding capability as a source of animals to be released; 3) synthesizing an understanding of the environmental history of the Chihuahuan Desert; and 4) choosing appropriate initial sites in northern Mexico and the United States for restoration. Securing the populations of the tortoise in its current range in the Bolson de Mapimi is crucial. Despite the fact that a 320,000 hectare Biosphere Reserve exists in Mapimi, only 40 hectares are actually owned and fenced by the Durango Institute of Ecology (Instituto Ecologia), Desert Laboratory. The remaining land includes large private ranches and ejido (collective agricultural communities). We are working to facilitate the acquisition of 6840 hectares of tortoise habitat adjacent to the Desert Laboratory. This will help to achieve sustainable conservation of a significant tortoise population within the Biosphere Reserve and provide a stable site for further long-term ecological studies that are necessary to inform large-scale reintroduction. In the fall of 2006, 30 Bolson tortoises were translocated from the Audubon Appleton-Whittell Research Ranch in Elgin, Arizona to Ted Turner’s Armendaris Ranch in south-central New Mexico, a Chihuahuan desert environment within the prehistoric range of this species. These tortoises, known as the Appleton tortoises in commemoration of Ariel Appleton, a champion of Bolson tortoise conservation, were originally brought to Arizona from Durango, Mexico by David Morafka in 1973. This population will be a source of animals available for future reintroduction. Ongoing studies of these animals, under semi-wild conditions will also contribute to a better understanding of ecology and reproduction outside the species’ current restricted range.
Added by: Sarina Wunderlich |