1999 

 OUR LIVING OCEANS 



SPECIES AND STATUS 



Atlantic Region 



Historical data on the size of sea turtle popu- 

 lations are limited or nonexistent. Complicatini; 

 the question ot population size is the need for a 

 long time-series ot data to understand the popu- 

 lation dynamics ot these species which have com- 

 plex lite histories. Standardized surveys of" selected 

 nesting beaches were implemented in the United 

 States in the late 1980's. These surveys, which 

 count the number of nests laid per year, provide 

 an indirect estimate of the adult female popula- 

 tion and an indication of whether this population 

 is declining, stable, or increasing. 



In recent years, our knowledge of sea turtle 

 biology has been enhanced by the use of tools to 

 understand the genetic identity of different nest- 



ing assemblages. Three subpopulations of logger- 

 heads have been identified in the southeastern 

 United States, and a fourth nests along the Yucatan 

 coast of Mexico. Adult and immature turtles from 

 these four subpopulations mix with each other on 

 the foraging grounds. Most loggerhead nesting oc- 

 curs along Florida's east coast where the annual 

 number of nests deposited has remained relatively 

 stable (about 65,000 nests/year), with evidence of 

 some increases in recent years. In contrast, nest- 

 ing of the sulipopulation north of Cape Canaveral, 

 Florida, has continued to decline (about 6,700 

 nests/year), and little is known about the small 

 subpopulation that nests in the Florida Panhandle 

 (about 500 nests/year). 



The Kemp's ridley inhabits coastal waters 

 throughout the Mid- and southeast Atlantic and 

 the Cjulf of Mexico. The Kemps ridle\- rs unusual 

 in that it nests almost exclusiveh' along one stretch 



Table 25-1 



Status and trends of princi- 

 pal sea turtle nesting popu- 

 lations in the U.S. Atlantic 

 and Pacific regions. 



Region and species 



Atlantic region 



Loggerhead, northern subpopulation-' 



Loggerhead, southern Florida subpopulation' 



Loggerhead. Florida Panhandle subpopulation-' 



Green"" 



Kemp's ndley^ 



Leatherbacl<'' 



Hawksbill' 

 Pacific region 



Loggerhead^ 



Green^ 



Olive ridley '° 



Leatherback" 



HawksbiH'^ 



Northern Florida-North Carolina 



Central Florida-southwest Florida 



Florida Panhandle 



Florida 



Mexico 



Florida, U S Virgin Islands, Puerto Rico Unknown 



U S Virgin Islands. Puerto Rico 



Japan 



Hawaii, Mexico 



Mexico. Costa Rica 



Mexico, Costa Rica. Maylasia. Irian Jaya Unknown 



Hawai 



'Sea tuflles in the U S Atlantic and Pacific regions originate from nesting populations in the U S and foreign countries 



-T = threatened E - endangered 



^Estimated total number of nesting females in the population based on 4 1 nests/female/year and a 2 S-year remigration interval 



'^Average -■■-■t^f-  --< ♦r.males nesting annually based on 3 5 nests/female/year for 1993-97 



^Numbe' 'Sting in 1997 based on 2 5 nests/female/year 



^Average ..jn-L/e tmales nesting annually based on 5 3 nests/female/year for 1993-97 for Florida, Sandy Point (U S Virgin Islands), and Culebra 



Island [Puerto Rtcof 

 'Average number of females nesting annually based on 4 5 nests/female/year for 1994-98 for fvlona Island (Puerto Ricol Nesting also occurs at other 



beaches in Puerto Rico and the U S Virgin Islands 



"Estimate of current Japanese nesting population is an aggregate of 1995 survey results for principal nesting beaches 

 ^Estimate of current total Hawaiian nesting population is based on doubling the estimate of nesters at East Island in 1997. Despite growth in the 



Hawaiian nesting population, concern remains over the increasing incidence of fibropapillomatosis The trend of the nesting population in fVlexico is 



decreasing 

 "^Estimated number of nesters at La Escobilla beach, Oaxaca. fylexico, m 1996 Nesting also occurs at other beaches in Mexico and in Costa Rica 

 ' 'Current nesting population estimate is for Mexico only, and based on an estimated 5,222 nests m 1996 on principal nesting beaches 

 ^^Current nesting population estimate for Hawaii is based on surveys through 1997 by the U S Fish and Wildlife Service 



262 



