just as there are in any other model. At some level, the 

 decision for headstarting is based upon the following three 

 mathematical relationships. Survivorship of captive turtles 

 during the first year of life (that is, from the time the eggs 

 are gathered on the beach until the time the yearling headstarted 

 turtles are released) is greater than or equal to the 

 survivorship of wild turtles during the first year of their 

 lives. This is the basis of headstarting programs, and it does 

 express a mathematical relationship even though the survivorship 

 is usually not expressed as any particular quantitative measure. 

 A second assumption is that survivorship of captive turtles after 

 their release is greater than or equal to the survivorship of 

 wild turtles after their first year of life. And finally, the 

 third assumption is that the fecundity of headstarted turtles 

 upon reaching adulthood is equal to the fecundity of wild 

 turtles. 



The first of these three model statements, that survivorship 

 from egg to release of yearlings is greater than or equal to 

 survival in the wild, might be easily shown to be true. However, 

 I do not know of any study that has compared natural mortality 

 (from the time eggs are laid to the end of the first year of 

 life) to mortality of headstarted turtles reared from eggs 

 gathered on the same beach. 



The third statement, that fecundity of headstarted turtles 

 upon reaching adulthood is equal to the fecundity of natural 

 turtles from the same population, might reasonably be assumed to 

 be true. [Although one must be aware of possible effects of 

 temperature on the incubation of the eggs, imprinting, and other 

 possible, but as yet unknown, effects] . 



About the relationship expressed in the second statement, 

 that survivorship of headstarted yearlings released into the wild 

 is equal to or greater than survivorship of wild yearling 

 turtles, we know very little. We do know that headstarted 

 turtles can survive in the wild after their release. But do they 

 survive as well or better than their wild counterparts? We do 

 not know. If they do not survive as well, does the presumed 

 increased survival during the first year of life in captivity 

 make up for the decrease in survival later on? Again, we do not 

 know . 



Yet those who headstart turtles rely on these mathematical 

 relationships, or some combination of them, when selecting this 

 management option. Even if such mathematical relationships are 

 not stated explicitly when the decision is made to select 

 headstarting as the management option of choice, this population 

 model lies hidden within the assertion that headstarting is 

 better than not headstarting. The important point that I want to 

 make here is that headstarting is based on an underlying 



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