Loggerhead Turtle (Caretta caretta) 



Status Report of the Loggerhead Turtle ( LI ewel lyn 

 M. Ehrhart) 



Introduction 



The expressed purpose of WATS II is "to present available 

 data on the status and exploitation of the six sea turtle species 

 in the western Atlantic," and insofar as the loggerhead turtle 

 ( Caretta caretta) is concerned, there is a wealth of new 

 information with which to deal. First, the data from the first 

 Western Atlantic Turtle Symposium have been adroitly compiled and 

 summarized by the editors of the Proceedings of WATS I. I intend 

 to draw heavily on that work in this review and, at the outset, 

 acknowledge the useful contribution of those editors (Bacon, 

 Berry, Bjorndal, Hirth, Ogren and Weber) . Second, the 

 independent scientific community has produced, in the past four 

 years, research results that constitute significant gains in our 

 understanding of the biology of the loggerhead, and of its 

 conservation and management. In my judgement some of the most 

 useful works are those of Richardson and Richardson (1982) ; 

 Frazer (1983, 1984, 1986, 1987b); Murphy and Hopkins (1984); 

 Witherington (1986); Kenwood (1987); Grouse et al. (1987) and, of 

 course, the late Archie F. Carr (1986a, b; 1987) . In several 

 papers published just prior to his passing, and posthumously, 

 Professor Carr brought together a myriad of systematic 

 observations, quantitative data and incandescent insight in a 

 synthesis that furthers our understanding of loggerhead ecologic 

 geography in the western Atlantic by an order of magnitude. 

 Concepts developed by Dr. Carr (1986a, b; 1987) , demonstrate the 

 complexity of loggerhead life history and, perhaps, begin to 

 convey the message that there are strategically important stages 

 to which the focus of management and conservation practice should 

 turn. 



The complexity that we are now beginning to appreciate in 

 loggerhead life history imputes a necessity to choose among the 

 several life history stages for the one (or ones) most useful in 

 assessing relative population stability, which I take to be the 

 fundamental objective of a status review such as this. Meylan 

 (1982) dealt thoroughly with this issue and concluded that, 

 because of the logistic difficulties presented by seasonal and 

 ontogenetic changes in habitat utilization by other stages, the 

 most practical approach to censusing sea turtles is to enumerate 

 females on nesting beaches. Estimates (and in some cases true 

 censuses) of the number of females emerging annually to nest can 

 be made "without excessive logistical difficulty" (Meylan 1982), 

 and it is reasonable to regard that number as an index to adult 

 survivorship and the culmination of our efforts to manage and 

 conserve. I concur that censusing nesting females continues to 

 provide the best index to population stability and intend to base 



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