dumping. Efforts should be made to determine the origin of such 

 trash and, whenever possible, to prosecute the agents responsible 

 for its presence. 



Construction may deter or prevent females from coming 

 ashore, as it did on Hutchinson Island, where a cofferdam 

 offshore was a barrier to turtles swimming along the shoreline 

 (Williams-Walls et al. 1983). 



Shadincf of Nesting Beaches 



Behind many nesting beaches high buildings or tall trees may 

 cast significant amounts of shade onto the beach (Coston-Clements 

 and Hoss 1983) , especially when the shoreline is oriented north 

 and south (as is the case along most of Florida's coastline). In 

 fact, enough shade might be created — especially at those beaches 

 that were originally backed only by low vegetation — to lower sand 

 temperatures to the point where masculinization of hatchlings 

 occurs. This possibility warrants further investigation. 



Predation Upon Eggs and Hatchlings 



Levels of predation upon eggs and hatchlings vary from one 

 beach to another. Human beings are among the most destructive 

 predators, and in some localities every egg clutch not 

 transferred to a hatchery is poached. 



The most destructive non-human predators are generally those 

 species whose presence at the nesting beach is a relatively 

 recent phenomenon, attributable either directly or indirectly to 

 human activity. Man plays an obvious role in the introduction of 

 domesticated animals such as dogs, pigs, cats, etc. But even 

 raccoons, which we think of as "wild" animals, have become 

 abundant in some coastal areas primarily because, in altering the 

 habitat, man has made it more suitable for them. 



On the other hand, and contrary to popular opinion, 

 mortality caused by "natural" predators, such as birds, crabs, 

 lizards, etc., is often relatively innocuous at an undisturbed 

 nesting beach (Mortimer 1981, 1984; Witherington 1986). Perhaps 

 this is because most of these predators have co-existed with 

 turtles for a long time and a balance has been reached. 



Much more research is needed to quantify what levels of 

 predation occur on nesting beaches, and also in the offshore 

 habitat. More effective methods of predator control also need to 

 be devised for those situations where predation truly is a 

 problem. 



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