Control of Terrestrial Predation 



Under some circumstances, such as when poaching is severe, 

 the best policy may be to transfer egg clutches to artificial 

 hatcheries. Such efforts are very labor intensive, however. 

 Another disadvantage of hatcheries is that their rates of 

 hatching success are often lower than are those of undisturbed 

 natural nests on the same beach. Moreover, at nesting beaches 

 where thousands of egg clutches are produced each season, 

 translocation of every clutch is not feasible. The best 

 solution, in such cases, may be to deal directly with the 

 predators . 



Ten years ago, at Tortuguero, Costa Rica, feral dogs 

 destroyed as many as 40% of the egg clutches laid on certain 

 parts of the beach (Fowler 1979) . The guards of the Tortuguero 

 National Park have since mounted a very successful dog 

 eradication campaign, and feral dogs have been virtually 

 eliminated from the area. 



Similarly, at one time, raccoons destroyed almost every egg 

 clutch laid at certain beaches in the United States. After much 

 trial and error, investigators finally devised the following 

 effective method of controlling raccoon predation (Hopkins and 

 Murphy 1983; S. Murphy, pers. comm.). At the beginning of each 

 nesting season, as many raccoons as possible are destroyed — 

 usually they are either trapped or shot. Then each morning 

 during the nesting season, a four or five foot square piece of 2 

 X 4 inch mesh welded wire is placed over the center of each new 

 nest, anchored at the corners, and covered with a layer of sand. 

 The beauty of this technique is that the egg clutch is not 

 disturbed, and the hatchlings are free to emerge from the nest on 

 their own. Moreover, it is a relatively simple procedure. 



Headstarting Turtles 



Headstarting is an experimental management measure in which 

 hatchling turtles are raised in captivity until they are large 

 enough to escape the jaws of most predatory fish and birds; then 

 they are released. Headstarting is not yet a proven management 

 measure. We now know that at least some headstarted turtles are 

 able to survive in the sea for a number of years. Unfortunately, 

 we also have numerous documented cases of headstarted turtles 

 that have washed ashore in a moribund condition, have been 

 recovered walking across parking lots in south Florida or have 

 even swum up alongside boats, apparently after having become too 

 habituated to human beings. We still do not know whether 

 survival among headstarted turtles is, in fact, any higher than 

 survival among turtles that enter the sea as hatchlings. 



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