UNIT 24 



SEA TURTLES 



109 



INTRODUCTION 



Sea turtles are highly migratory and ply the 

 world's oceans. Cinder the Endangered 

 Species Act of 1973, all marine turtles are 

 listed as endangered or threatened (Table 

 24-1). The NMFS has authority to protect 

 and conserve marine turtles in the seas and 

 the U.S. Fish and Wildlife Service main- 

 tains authority while turtles are on land. 



The Kemp's ridley, hawksbill, and leath- 

 erback turtles are listed as endangered 

 throughout their ranges. The loggerhead 

 and olive ridley turtles are listed as threat- 

 ened throughout their U.S. ranges, as is the 

 green turtle, except the Florida nesting 

 population which is listed as endangered. 



T = Listed under the Endangered Species Act as threatened 

 2 E ■ Listed under the Endangered Species Act as endangered 

 Endangered in Florida, threatened elsewhere in the US Atlantic. 

 4 Using t 5 nests/female . 



5 Declining at an average rate of 3%/year since 1978 



historical level for Hawaii only, current level is 2,000 in Hawaii and 100-300 in American Samoa; current level in Guam is unknown 

 'Trend in Hawaii only, monitored at French Frigate Shoals, however, great concern exists over increasing frequency of libropapilloma 

 disease in all Hawaiian green turtles 

 8 Current abundance in Hawaii; current abundance in Guam and American Samoa is unknown 



SPECIES AND STATUS 



The six Pacific species are loggerhead, 

 green, Kemp's ridley, leatherback, hawks- 

 bill, and olive ridley turtles. All six are also 

 found in the Atlantic Ocean, but the olive 

 ridley does not enter (J.S. waters. In Hawai- 

 ian waters, the green and hawksbill are 

 most abundant. Off the U.S. west coast, the 

 loggerhead, leatherback, and olive ridley 

 turtles are most commonly reported. 



Historical data on sea turtle numbers are 

 limited. In addition, the length of time that 

 data have been collected has been short 

 when compared with the long life and low 

 reproductive rate of all turtle species. It is 

 difficult to assess the long-term status of 

 sea turtles owing to the limited data. 



The 1982-84 number of loggerhead nest- 

 ing females from North Carolina to Florida 

 was 1 8,000-2 1 ,000 (Table 24-1 ) . Most nest 



along Florida's east coast where nest num- 

 bers have been stable for five years. Only 

 about 700 female Kemp's ridley turtles 

 nest along a limited portion of Mexico's 

 Atlantic coast. In 1947, on a single day, 

 40,000 females were seen nesting on one 

 beach alone. The documented decline in 

 the Kemp's ridley is probably indicative of 

 dropoffs for other sea turtles, though the 

 periods of their various declines may have 

 differed (Fig. 24-1). 



Historically, the green sea turtle has sup- 

 ported large fisheries along the Florida and 

 Texas coasts, although its nesting on (J.S. 

 beaches has probably always been limited. 

 In the late 1800's, 2,000 females reportedly 

 nested at Key West, Fla. Currently, per- 

 haps 600-800 green turtles nest along the 

 Florida coast. However, it appears that the 



