elsewhere in the WATS region, but Kaufmann (1975) reported that 

 some Colombian loggerheads nested at least four times. He gave 

 no estimate of the mean. The broad-scale purposes of this review 

 make it necessary to adopt a working hypothesis about mean clutch 

 frequency. Though there is clearly considerable annual variation 

 in this trait, my subjective evaluation of the data cited above 

 has led me to accept Murphy and Hopkins' (1984) 4.1 nests per 

 female as the current "best estimate," and I have adopted that 

 figure for the purposes of this review. 



The matter of mean remigration interval is, if anything, 

 even more ambiguous. Meylan (1982) and Hughes (1982) have 

 pointed out the problem of low observed remigration percentages 

 world-wide. A corollary to this involves the impossibility of 

 knowing if a tagged female that fails to reappear has died or is 

 simply nesting unnoticed on some other beach. After all, 

 evidence is abundant that some loggerheads move considerable 

 distances between successive nestings (Bjorndal et al. 1983) . 

 Even in the southeastern U.S., beach coverage is so patchy that 

 the probability of observing a female that happens to nest on a 

 beach a few kilometers from any particular research area is far 

 less than 50%. Given this gross imprecision in our ability to 

 assess mean multi-annual cycle length, it seems best to resist 

 the temptation to extrapolate the number of females nesting per 

 year to the total adult female population. Rather, it is more 

 useful to monitor nesting aggregation size each year and analyze 

 the patterns and trends in the variation observed. That can be 

 done, I believe, for very large expanses of nesting beach by the 

 methods pioneered by Carr and Carr (1977) , improved by Shoop et 

 al. (1985), and perfected by Murphy and Hopkins (1984). 



Should a reason arise to derive an estimate of the total 

 adult population, much evidence exists to show that two and three 

 year cycles clearly predominate in western Atlantic loggerheads 

 (Richardson et al. 1978a; Bjorndal et al. 1983; Ehrhart 1980; 

 Lund 1986) . Two year cycles are seen most frequently and 

 intervals of just one year are negligibly few. Observed four 

 year cycles may include turtles that nested elsewhere in two 

 years but the evidence from Little Cumberland Island, Georgia, 

 indicates that some four year cycles are real (Richardson and 

 Richardson 1982). An estimate of 2.6 years is given in that same 

 work, as the mean remigration interval and I believe that to be 

 the current "best estimate." I am aware of Meylan' s (1982) 

 warning about annual variation in nesting activity and agree that 

 good estimates must incorporate consideration of that variation. 

 That is, surveys should be done annually over a number of years 

 to establish a baseline against which trends can be based. 

 Loggerhead nesting in the southeastern U.S. can vary by a factor 

 of approximately 2 (Conley and Hoffman 1987) , but never to the 

 drastic extent reported by Limpus (1982) for green turtles 

 nesting at Heron Island. I am aware also that any estimation of 

 total adult population size would involve multiplication by a 



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