736 



Fishery Bulletin 101(4) 



have not reached the Azores and they are younger than 

 our threshold ages. We beheve that mortality in this early 

 transitional stage when loggerhead sea turtles first cross 

 the Atlantic may be high. In addition to high rates of pre- 

 dation. winds and currents can overwhelm the swimming 

 and orientation abilities of the posthatchling sea turtles, 

 transporting the turtles to habitats, such as waters off the 

 British Isles, that cannot sustain them (Carr, 1986; Hays 

 and Marsh, 1997). Generating directly derived estimates 

 of survival probabilities of loggerhead sea turtles younger 

 than 2 years of age should be a high priority. 



Acknowledgments 



This study would not have been possible without the sup- 

 port of our colleagues in the Azores: "Equipa Tartaruga" 

 at the Department of Oceanography and Fisheries (DOP), 

 University of the Azores; the captains and crews of the 

 commercial tuna fleet based in Horta and Pico; and J. and 

 G. Franck of the MY Shanghai. We thank M. Chaloupka 

 for encouragement to pursue catch-curve analysis. We 

 thank M. Chaloupka and J. Seminoff for comments on 

 earlier drafts of the manuscript and P. Eliazar for technical 

 assistance. This project was funded by the U.S. National 

 Marine Fisheries Service and the Disney Wildlife Con- 

 servation Fund. All work was conducted in compliance 

 with the Institutional Animal Care and Use Committee, 

 University of Florida. 



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