120 



ReptiUw iinj AinphihiLins — i)tfi' Lntni^ Resources 



Barbour's iiui(> lurtle (Graplemys harbouri) is restricted to the Apalachicola River system of 

 Alabama. Florida, and Georgia. The species is a candidate for listing under the Endangered 

 Species Act. 



species (Dodd and Fiunz 1993). The alarming 

 decline of marine turtle populations is discussed 

 later in this section. 



Perhaps the best data on long-term popula- 

 tion changes in turtles are for the diamondback 

 terrapin {Malaclemys terrapin), a species 

 exploited heavily during the 19th century as a 

 gourmet food (McCauley 1945; CaiT 1952). 

 Terrapin populations declined rapidly, causing 

 some states to set seasons and limits for their 

 protection as early as 1878. The market for ter- 

 rapin meat eventually waned, and terrapin pop- 

 ulations recovered somewhat because their 

 habitat remained largely intact. Unfortunately, 

 some terrapin populations may be declining 

 again because of renewed regional harvesting 

 (Garber 1988). increased habitat destruction, 

 mortality from vehicles, and drowning in crab 

 traps (Ernst et al. 1994). 



Some turtle species, such as members of the 

 map turtle genus Graptemys. have restricted 

 ranges (Lovich and McCoy 1992) that place 

 them at extreme risk of extinction. In addition, 

 the popularity of many species, particularly tor- 

 toises, as pets, contributes to the decline of wild 

 populations (lUCN/SSC 1989: Ernst et al. 

 1994). Disease also appears to contribute to 

 population declines in some turtles (Balazs 

 1986; Dodd 1988; Jacobson et al. 1991) and 

 even seems a major challenge to the recovery of 

 the federally threatened desert tortoise (USFWS 

 1993). 



Because of individual longevity, delayed 

 maturity, and long generation times of turtles, 

 long-term studies are required to monitor the 

 dynamics of turtle populations (Gibbons 1990); 

 recovery of most threatened species will be 



slow. Programs in which hatchlings are propa- 

 gated in captivity and later released into the 

 wild will do little to assist the recovery of turtles 

 until the ultimate causes of decline are correct- 

 ed (Frazer 1992). 



Efforts to conserve turtles in the United 

 States should be concentrated in areas of high 

 species diversity, where many species have lim- 

 ited distributions, and where populations are at 

 great risk. Ni)table high-risk areas include shal- 

 low wetlands inhabited by freshwater turtles 

 and coastal zones occupied by sea turtles. The 

 most significant area of turtle endemism in the 

 United States is along the Coastal Plain of the 

 Gulf of Mexico (Lovich and McCoy 1992). 

 Eleven species of turtles in the southeastern 

 United States, where diversity is high (Iverson 

 and Etchberger 1989; Iverson 1992), require 

 conservation action, adding to the importance 

 of implementing immediate conservation pro- 

 grams in that region. 



References 



Balazs. G.H. 1986. Fibropapillomas in Hawaiian green tur- 

 tles. Marine Turtle Newsletter .^9: 1-,^. 



Brooks, R.J.. G.R Brown, and D.A. Galbraith. 1991 . Effects 

 of a sudden increase in natural mortality of adults on a 

 population of the common snapping turtle (Chelydra ser- 

 pcnimci). Canadian Journal of Zoology 69:1314-1.^20. 



Brooks. R.J., D.A. Galbraith. E.G. Nancekivell. and C.A. 

 Bishop. 1988. Developing guidelines for managing snap- 

 ping turtles. Pages 174-179 in R.C. Szaro, K.E. Severson, 

 and D.R. Patton, tech. coords. Management of amphib- 

 ians, reptiles, and small mammals in North America. 

 U.S. Forest Service Gen. Tech. Rep. RM-166. 



Carr. A.F. 19.S2. Handbook of turtles. The turtles of the 

 United States, Canada, and Baja California. Comstock 

 Publishing Associates, Cornell University Press, Ithaca, 

 NY. 542 pp. 



Collms, D.E. 19911. Western New York bog turtles: relicts of 

 ephemeral islands or simply elusive' Pages 151-153 in 

 R.S. Mitchell, C.J. Sheviak, and D.J. "Leopold, eds. 

 Ecosystem management: rare species and significant 

 habitats. Proceedings of the Fifteenth Annual Natural 

 Areas Conference. New York State Museum Bull. 471. 



Congdon. J.D.. A.E. Dunham, and R.C. Van Loben Sels. 

 1993. Delayed sexual matunty and demographics of 

 Blanding's turtles (Emydoiileu blandingii): implications 

 for conservation and management of long-lived organ- 

 isms. Conservation Biology 7:826-833. 



Dodd. C.K.. Jr 1988. Disease and population declines in the 

 flattened musk turtle Slemolbenis depressus. American 

 Midland Naturalist 119:394-401. 



Dodd, C.K.. Jr. and R. Franz. 1993. The need for status 

 information on common herpetofaunal species. 

 Herpetological Review 24:47-49. 



Ernst. C.H., J.E. Lovich. and R.W. Barbour 1994. Turtles of 

 the United States and Canada. Smithsonian Institution 

 Press. Washington, DC. In press. 



Frazer, N.B. 1992. Sea turtle conservation and halfway 

 technology. Conservation Biology 6:179-184. 



Garber, S.B. 1988. Diamondback terrapin exploitafion. 

 Plastron Papers 17(6): 18-22. 



Gibbons, J.W., ed. 1990. Life history and ecology of the 

 slider turtle. Smithsonian Institution Press, Washington, 

 DC. 368 pp. 



Honegger, R.E. 1980. List of amphibians and reptiles either 

 known or thought to have become extinct since 1600. 

 Biological Conservation 19:141-158. 



