Turtles in Trouble: The World's 25+ Most Endangered - Wildlife ...

Turtles in Trouble: Top 25+ Endangered Tortoises and Freshwater Turtles—2011Other Top 40 Tortoises and Freshwater Turtles at Very High Risk of ExtinctionBolson TortoiseGopherus flavomarginatus Legler 1959; Family TestudinidaeNorth America: Mexico (Chihuahua, Coahuila, Durango); Introduced: USA (New Mexico)IUCN Red List: VU, Vulnerable A1cd; TFTSG Draft: EN, Endangered; CITES: Appendix IOnly known to science since the late 1950s, this speciesis found in a very small region of the Chihuahuan Desert. Itis the largest North American tortoise, reaching over 45 cmin shell length, yet is the least known. Previously somewhatimpacted by domestic pet trade, but more by hunting for localconsumption, the species is now mainly threatened by habitatconversion into agricultural land for biofuel production andcattle ranching. The recent proliferation of water wells, stocktanks, irrigated corn fields, and increased cattle stocking notonly degrades this hyper-arid habitat, but the water providessubsidy for predators of eggs and juveniles. Previously alsooccurring in New Mexico and Texas during the Pleistocene,this species has been suggested for possible reintroductioninto portions of its former range in Mexico and the USA.Gopherus flavomarginatus, Mexico. Photo by Eric V. Goode.Bog TurtleGlyptemys muhlenbergii (Schoepff 1801); Family EmydidaeNorth America: USA (Connecticut, Delaware, Georgia, Maryland, Massachusetts, North Carolina, New Jersey, NewYork, Pennsylvania, South Carolina, Tennessee, Virginia)IUCN Red List: EN, Endangered A1cd+2cd; TFTSG Draft: CR, Critically Endangered; CITES: Appendix IAt a maximum size of 11.5 cm shell length, the Bog Turtleis one of the world’s smallest turtle species. It occurs in highlyfragmented small populations in spring-fed fens and marshes.It lost the great majority of its suitable habitat in historic andrecent times through conversion to agricultural land and drainage;it has suffered further impact from past collection for thepet trade, and possibly roadkill and increased predation rates.Recent observations of disease outbreaks, and the prospect ofclimatic change, represent unquantified but potentially severeimpacts on the horizon. Due to the species’ highly fragmentedoccurrence in habitats subject to vegetational succession, intensivemanagement is needed to retain existing populations.Restoration of former habitat, and creation of alternative sites,is challenging, while the species’ low reproductive output (onaverage under 4 eggs/year per mature female) means recoveryis a slow gradual process at best.Glyptemys muhlenbergii, USA. Photo by Maurice Rodrigues.– 50 –