observations. One of the most significant parameter is the 

 average age to reach maturity, which we assume is around eight to 

 ten years (Marquez, in prep.)* The total mortality from egg to 

 adult can be deduced using the incubation mortality and the total 

 adult mortality assessed by tagging, recapture and consecutively 

 (tagged females) observed at the nesting beaches. This method 

 has its shortcomings but it is the only one available to date. 

 In this way the life cycle and theoretical population changes are 

 truly represented and may be graphed. (Marquez et al. 1982; 

 Marquez, in prep.). 



Re-stockincf Program 



How and when the Kemp's Ridley Program was started has been 

 described previously (Montoya 1966; Chavez et al 1967; Pritchard 

 and Marquez 1973; Marquez 1983, 1984 in prep; Marquez et al. 

 1985a, b) . The main purpose of the program is to restore the 

 species to its maximum possible population levels. For the time 

 being the imminent threat of extinction that hangs over the 

 species has been avoided. To consolidate these results more 

 research and conservation work are needed. 



The program has run for 22 consecutive years. During the 

 last ten years, the results have doubled partially as the result 

 of a cooperative program between the Institute de Pesca, the U.S. 

 Fish and Wildlife Service and the National Marine Fisheries 

 Service. The main objective of this effort was to improve the 

 status of the species throughout its geographic distribution, and 

 especially within the Gulf of Mexico, by trying to establish 

 nesting areas on Padre Island, Texas. For the last ten years, 

 this has been conducted under the MEXUS-Golfo Program, and the 

 results of this period are shown in Table 1. These results have 

 doubled those of the 1966-1977 period. During the first period 

 3,803 nests were protected resulting in 273,614 hatchlings; 

 during the second period from 1978 to 1986, 7,245 nests were 

 protected resulting in 474,723 hatchlings. From the sum total of 

 hatchlings (748,377) more than 97% have been released directly on 

 Rancho Nuevo and up to 1986, 6,327 hatchlings have been used in 

 the Padre Island Project. 



The mean number of eggs (Y) per nest has slightly fallen 

 with time (X) , and this tendency can be deduced by the following 

 linear regression: 



Y = 109,554 - 0.433X 

 r = - 0.704 



Older and larger organisms generally lay more eggs than younger 

 ones. This is in agreement with the results from the equation 

 above. In 1966, when the research and conservation was begun we 

 found a Kemp's ridley population made up mostly of aged 



162 



