one thousand nests per year during the early 1980s, the general 

 trend has been downward. 



(2) Rate of change. 



By calculating the rate of change of the number of olive 

 ridley nests laid each year, a fair approximation of the rate of 

 change in population numbers of nesting females could be 

 obtained. The Surinam nesting data over the past 20 years should 

 be suitable for a rough regression analysis to obtain this rate, 

 but this has not yet been done. Data for other western Atlantic 

 olive ridley populations are inadequate for such an analysis. 



(3) Ability to recover. 



With the currently low numbers, how the Surinam olive ridley 

 population can recover is difficult to see. The criteria for a 

 healthy nesting population are present: the beaches are 

 currently in an even better condition than during the late 1960s, 

 when there were greater numbers of olive ridleys, and 

 conservation management in Surinam may be the best in the world. 

 No obvious terrestrial reason explains the precipitous decline of 

 the Surinam population. In the face of overwhelming evidence to 

 the contrary, there is the slight hope that a diffusion of 

 nesting females is taking place to other beaches in French 

 Guiana, or if the hypothesis of west African origin is correct, 

 maybe they are filtering back toward their ancestral home region. 

 Whatever the case, no reason in the past 20 years in Surinam 

 explains the cause for the decline there. The ability to recover 

 must be found in reducing the assumed excessive, man-induced 

 mortality at sea. 



Mortality 



(1) At sea. 



The most devastating damage being done to the olive ridley 

 populations in the western Atlantic is almost certainly caused by 

 the shrimp boats. This is almost self-evident, since they share 

 the same food and foraging grounds — namely crustaceans and their 

 habitat. 



Shrimp boats of several nations fish off the coasts of the 

 Guianas and Venezuela. Their cumulative incidental take is not 

 commonly known or available but circumstantial evidence suggests 

 that it must be considerable. In the late 1960s, during 

 experimental trawling exercises along the coast of the Guianas, a 

 single ship caught 39 olive ridleys in a one year period, even 

 though olive ridleys were not the target species, and the ship 

 trawled only periodically. 



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