A rough estimate places some 90-100 shrimp boats of French, 

 German, Japanese and U.S. origin off the coast of French Guiana. 

 An ex-crewmember reported that they usually had a cumulative 

 incidental catch of 2-3 olive ridleys per day. Data are not 

 available on what is being caught on the foraging grounds at the 

 mouth of the Orinoco River, but the large number of tag returns 

 from that area during the studies by Pritchard and Schulz is 

 indicative of a considerable mortality factor there. 



Furthermore, and often ignored in mortality analyses, along 

 the Surinam and Guyana coast set nets, often several kilometers 

 long, are used by local fishermen. Olive ridley mortality caused 

 by these lethal barriers is unknown, but it could be 

 considerable. 



(2) On the beach. 



In Guyana many olive ridleys are killed on the beaches. 

 Carcasses form ample evidence. The full extent of this carnage 

 is unknown, because many olive ridleys are carried off alive and 

 slaughtered elsewhere for local consumption or sale in markets. 



In Surinam, olive ridleys are fully protected, and poaching 

 is not evident. Some natural mortality probably occurs among 

 nesting adults; some may be dragged off by jaguars. Finding a 

 dead specimen on the beach or evidence of a kill is rare. 



Egg and hatchling mortality is a different matter. From 

 example of 100 olive ridley nests in Surinam, 60 were attacked by 

 ghost crabs within a few days after having been laid, destroying 

 an average of 12% of the eggs, although some nests were 

 completely destroyed. 



A major mortality factor in Surinam is beach erosion. 

 Surveys have shown, that about 25% of the nests are destroyed in 

 this manner. For this reason, one of the major activities of the 

 Surinam conservation program is the translocation of such doomed 

 nests to safer beach locations. 



Hatchling mortality is speculative for all sea turtle 

 species. Of the newly hatched sea turtles 1% or less is 

 estimated to survive for more than a few weeks. Another pseudo- 

 statistic used is that less than one tenth of one percent of the 

 eggs will ever become an adult turtle. These numbers are often 

 quoted in the popular press as well as in the scientific 

 literature, but no factual basis can be found for this. 



A compelling argument to be used in explaining the decline 

 of the Surinam olive ridleys may be the excessive harvest by the 



179 



