Campeche. In either case, it seems they look for shallower 

 waters, where crustaceans are abundant, especially crabs. 



Populations 



In the 1950s, the Kemp's ridley was one of the most abundant 

 sea turtles in the Gulf of Mexico as indicated in a 1947 film 

 where more than 40,000 females were estimated by Carr (1963) and 

 Hildebrand (1963) to have come ashore at Rancho Nuevo, in one 

 "arribada." In 1966, the first camp was installed at the nesting 

 beach (Montoya 1969) ; in that year and the two following years 

 more than 1,000 turtles came ashore during the "arribada." In 

 1968 Montoya and Vargas (pers. com.) estimated an "arribada" of 

 more than 2,500 females; (Pritchard and Marquez 1973, and pers. 

 obs. by Marquez 1967-1987) . Since then, the total number of 

 nesting females has decreased at a constant rate of 3.9% annually 

 (Marquez, in prep.), and during the last five years no "arribada" 

 has had more than 200 females. 



The total population (P) is calculated according to the 

 number of nests (N) produced each year at Rancho Nuevo, and 

 multiplied by the nesting cycle (C = 1,724) and considering a 1 

 to 1 male-female relationship (R) , divided by the total fecundity 

 of each female (F = 1,326) (Marquez et al. 1982). The results 

 for 1987 are: 



P = (N C R)/F 



P = (854 X 1,724 X 2)/l,326 = 2,200 adults. 



According to calculations for the previous ten years, the highest 

 population that nested at Rancho Nuevo was 2,634 turtles in 1979, 

 and the lowest 1,929 in 1985. These figures are estimated to 

 represent 80% of the total nesting population; the rest disperses 

 throughout the coast from South Padre Island, Texas, to Isla 

 Aguada in Campeche, Mexico (Marquez and Fritts 1987) . Small 

 nesting concentrations occur at three other sites: Playa 

 Washington, Tamaulipas, a few kilometers from the border with the 

 United States; around Cabo Rojo and between Tecolutla and Boca 

 Lima both in Veracruz. At this last beach, nests are being 

 relocated (10 to 15 nests) by the Fisheries Inspector, Mr. 

 Fernando Manzano (WATS II National Report) . Apparently, limited 

 nesting for L. kempi occurs at South Padre Island, Texas, and 

 east of Isla Aguada, Campeche, where in some years two or three 

 nests have been recorded. 



The abundance of adults, as stated in the previous 

 paragraph, can be evaluated by counting the nests at the main 

 nesting beach. Eggs and hatchlings can also be directly 

 evaluated to measure reproduction that occurs each year. 

 However, other development stages, for example juveniles and pre- 

 adults, can also be assessed by using theoretical models, in 

 which you have to introduce assumptions, based partially on valid 



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