enterprises (Bonnet et al. 1985). Research assessing the impact 

 from this source of Ftj could be conducted through approaches 

 similar to those outlined for estimation of Fj. Research to 

 develop a permanent tag suitable for hatchlings is probably one 

 of the most critical needs of sea turtle management. Such 

 technology would not only shed information on impact from fishing 

 mortality but also would help answer the evasive management 

 question of how many hatchlings are needed to produce one nesting 

 female within respective stocks. The ramifications of having 

 suitable tag technology for the hatchling life history stage are 

 enormous in understanding sea turtle population dynamics in 

 general, and during the "at sea" stage in particular. 



"At sea" mortality of juveniles and adults ; "At sea" life 

 history stages are very difficult to study and, consequently are 

 those in most need of management attention. Opportunities to 

 conduct research on juvenile and adult sea turtles at sea are 

 unlike those for their onshore cohorts for whom data on Fj, Fjj 

 and FjY can be generated on the nesting beach where access to 

 eggs, hatchlings and nesters is more readily available and the 

 ability to control or characterize harvest substantially greater. 

 "At sea" stages constitute the longest and most inaccessible (to 

 the researcher) of all constituent life history stages. 

 Furthermore, a lack of information on sea turtles in these 

 offshore stages and their tendency to migrate across 

 international boundaries pose severe managerial problems. 

 Research to solve this management dilemma should be initially 

 focused on exploited stocks where access to valuable information 

 on stocks at sea is inherent in the fishery. Examples of 

 exploited stocks with tremendous research potential are the 

 directed olive ridley fishery operating out of Oaxaca, Mexico and 

 the incidental harvest of Kemp's ridleys by U.S. and Mexican 

 shrimp fleets. 



Research programs identifying rates of fishing mortality for 

 sea turtles at sea (Ftji and Fy) must be developed for directed 

 fisheries as well as incidental catch. Several research 

 alternatives appear applicable for generating at sea data on 

 directed and incidental fishing mortality among juvenile and 

 adult sea turtles. Among traditional methods deployed in finfish 

 fisheries which are transferable to exploited sea turtle stock 

 management are "fishing success" methods using catch and fishing 

 effort data -(DeLury 1951) . These can be improved with tag- 

 recapture data (Leslie and Davis 1939) . Such data can be used to 

 construct catch curves (if age is known) , estimate exploitation 

 rates, and calculate catchability coefficients as well as to 

 identify changes in stock abundance and size composition through 

 analysis of time series of catch and effort statistics. 



Data collection programs which incorporate onboard observers 

 have proven successful in estimating incidental sea turtle losses 

 in the southeastern U.S. shrimp fishery. Similar programs appear 



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