procedures are not employed when moving the clutch, however, 

 excessive egg mortality can occur. Eggs can be safely moved only 

 at those times during their development when the delicate extra- 

 embryonic membranes are least likely to be torn — i.e., within the 

 first six hours after they are laid, and during the second month 

 of incubation (C. Limpus, pers. comm.). Even then, the eggs must 

 not be rotated (especially after the first six hours) , nor should 

 they be moved quickly in any horizontal direction. Finally, the 

 clutch should be reburied so that its situation approximates as 

 closely as possible a natural nest. Whenever possible, the 

 hatchlings should be allowed to emerge naturally from the nest at 

 night and to make their way to the sea without human 

 interference. 



To prevent unnecessary egg mortality resulting from over- 

 manipulation, and to avoid wasting human labor, nests should only 

 be moved when they are in fact "doomed." Unless they will be 

 damaged by other agents, those egg clutches deposited above the 

 spring high tide line are probably best left in situ. 



Erosion Made Worse by Human Activity 



In recent years coastal erosion seems to be getting worse. 

 Some scientists believe that this is due to a general rise in sea 

 levels. If this is so, and it may well be, many nesting beaches 

 are likely to be in serious trouble and there may not be a great 

 deal that we can do about it. 



Some erosion, however, is exacerbated by human activities. 

 When calculating how much distance to put between their property 

 and the sea, developers frequently underestimate the forces of 

 erosion, not considering the prospect of intense storms or 

 hurricanes. They also build in places such as on barrier islands 

 which by nature are unstable. Then when the sea encroaches upon 

 their property they react by constructing sea walls or other 

 beach armoring structures. Unfortunately, such structures can 

 actually worsen erosion by deflecting the waves downward. 

 Eventually, the beach which had once separated the property from 

 the sea disappears and only the barricades remain, until they, 

 too, are destroyed by the sea. 



The mining of beach sand for human use can seriously damage 

 nesting habitat and should be prohibited. When too much sand is 

 removed, that which remains may be too shallow to allow nest 

 construction. Often the beach platform is lowered to the point 

 that it floods at high tide or during heavy seas, making it an 

 unsuitable incubating medium. 



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