Literaturdatenbank
Literaturdatenbank |
|
 |
|
Kuchling, G. , Two decades of western swamp turtle pseudemydura umbrina recovery through captive breeding and re-introduction. Unpublished paper presented at 6th World Congress of Herpetology.
Added by: Admin (21 Nov 2009 11:59:58 UTC) |
| Resource type: Conference Paper BibTeX citation key: Kuchling2008 View all bibliographic details  |
Categories: General Keywords: Australien = Australia, Chelidae, Fressfeinde = predators, Habitat = habitat, Pseudemydura, Pseudemydura umbrina, Schildkröten = turtles + tortoises Creators: Kuchling Collection: 6th World Congress of Herpetology |
Views: 3/846
Views index: 16% Popularity index: 4% |
| Abstract |
|
The critically endangered Western Swamp Turtle Pseudemydura umbrina is only known from seasonal clay swamps in the outskirts of Perth in Western Australia. Two small nature reserves were set aside for the species in the early 1960s and then harbored more than 220 individuals, but by the late 1980s the turtles had nearly disappeared from Twin Swamps Nature Reserve. Only about 30 wild individuals survived at the smaller Ellen Brook Nature Reserve, the last self-sustaining wild population. With 17 captive individuals that were not breeding the world population in 1987 counted less than 50 individuals. A successful captive breeding operation for P. umbrina at Perth Zoo started in 1988, the Recovery Team was formed in 1991 and a recovery plan was first published in 1994. Conservation actions include predator control like the construction of fox-proof fences to exclude foxes and dogs from turtle habitat; supplementing bore water into swamps during dry winters and springs to extend the duration of swamp live; changes of the drainage patterns of several swamps to increase flooding; fire management; captive breeding; and since 1994 re-introduction and introduction of captive bred juveniles into two nature reserves. Today the population at Ellen Brook Nature Reserve increased to about 70 individuals. About 160 juveniles were re-introduced at Twin Swamps Nature Reserve between 1994 and 2005, and about the same number to an introduction site, Mogumber Nature Reserve, since 2000. A trial introduction of 10 juveniles started in 2007 at a third site, Moore River Nature Reserve. However, after 14 years of re-introduction and introduction, climate change now poses a new difficult hurdle for the recovery of the species. Dryer winters make the seasonal swamp habitat in the two main release sites increasingly marginal. Today the population at Twin Swamps Nature Reserve may count about 40 individuals and virtually no successful recruitment has yet been recorded despite demonstrated egg production by re-introduced females. At Mogumber Nature Reserve about half of the then released turtles died in a wildfire in late 2002 and the majority of turtles have not yet reached maturity. Thus, although the captive population counts today about 200 and the number of wild P. umbrina is again over 200, long-term success (self-sustenance) of the re-introduced and introduced populations still could not be demonstrated.
Added by: Admin |