of nesting loggerheads along the southeastern U.S. For this 

 reason we observed the hawksbills at Pasture Bay, Antigua, for an 

 entire nesting season before we selected a tagging methodology. 

 Today, we are tagging our animals in three different ways, and we 

 are confident that the turtles are not being adversely affected 

 by our presence on the nesting beach. Given that the number of 

 safe nesting beaches are few and becoming more scarce with each 

 passing day throughout the Caribbean, we would be irresponsible 

 if, in our quest for knowledge, we drove turtles to nest on a 

 less protected beach and thereby to their destruction. Please 

 deal gently with nesting sea turtles, particularly while they are 

 ascending and descending the beach. Do not initiate tagging 

 programs on beaches unless you have specific goals in mind and 

 you are very careful about what you are doing. If you are going 

 to tag, use the best available tagging technology, so you don't 

 have to harass your turtles on subsequent nesting visits. 

 Research on better tag technology is always needed. 



Reproductive Success 



We know now many eggs are in an average clutch, but we know 

 very little about the proportion of hatchlings that emerge from a 

 given clutch or the proportion of emerged hatchlings that 

 successfully reach the water. We count nests and nesting crawls, 

 but all too often we do not follow the fate of those nests. Some 

 or most will be destroyed before they hatch. We know many 

 reasons for the losses (predators, erosion, excessive rainfall, 

 etc.), but rarely do we know how many nests are lost or what 

 proportion are associated with a particularly lethal factor. If 

 a nest does escape destruction, hatching success is rarely 100 

 percent, more usually 50 to 95 percent, depending on the species 

 of turtle involved and the beach conditions affecting the nest. 

 Reproductive success of natural nests is a most important aspect 

 of population biology and resource management, but the data are 

 generally not available. Research on reproductive success is 

 inexpensive and accessible to anyone with an active nesting 

 beach. Much more research is needed in this area. 



Temperature Modulated Sex Ratios 



No topic has captured the attention of the sea turtle 

 research community quite like Mrosovsky and Yntema's temperature 

 modulated sex ratio paper of several years ago. For those of us 

 brought up on the "birds and bees" school of sex education, the 

 lack of deterministic sex chromosomes in the fertilized egg of 

 sea turtles was an amazing revelation. Since then, the pivotal 

 temperatures for several species of sea turtles have been 

 determined, and the association of the phenomenon with natural 

 nests has been verified. However, ambient sand temperatures 

 fluctuate on the beach, and the relationship between these 

 fluctuating temperatures and sex determination remains poorly 

 understood. 



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