This provides information on the potential impacts of changes in 

 habitat quality and quantity which can cause changes in turtle 

 abundance. Critical habitats can be identified and managed as 

 necessary. 



Observer programs proximal sensing ; Placing observers on 

 vessels is the only way to obtain unequivocal evidence of turtle 

 catch and mortality either through direct fishery activities or 

 incidental to a non-turtle fishery. For example, Witzell (1984) 

 reported on the capture of sea turtles incidental to the Japanese 

 longline fishery in the U.S. Exclusive Economic Zone (EEZ) . 

 These data were provided both by the fishermen who were required 

 to report all incidental catches and by observers placed on these 

 vessels by the National Marine Fisheries Service. 



Perhaps the best known NMFS observer program obtained 

 information on the incidental capture of turtles in shrimp 

 trawls. An additional experimental trawling program provided 

 evidence on the capture and mortality of turtles in shrimp 

 trawls. These results led to the promulgation of regulations 

 requiring the use of a Turtle Excluder Device (TED) by shrimpers 

 beginning in the Cape Canaveral, Florida, Oct. 1, 1987. 



Entanglement in other types of fishing gear or with other 

 human activities, such as power plant entrainment have been 

 documented. However, quantitative information can only be 

 provided by direct and consistent efforts to collect data. This 

 includes placing observers in the field. 



Information Provided 



Both remote and proximal sensing techniques provide 

 information on stock boundaries and numerical trends. Direct 

 observations on shipboard provide information on mortality which 

 can be used to project population trends over time. When 

 significant sources of mortality are identified, then management 

 strategies, which mitigate mortality, can be developed . 



The quantity of pelagic environment has yet to be 

 determined. However, several existing projects have demonstrated 

 the qualitative importance of specific areas to turtles (Ehrhart 

 1983; Callazo and Boulon 1987; Ogren 1985). These studies all 

 deal with juvenile turtles that appear to be somewhat resident in 

 localized areas, and will provide information both on the quality 

 and quantity of habitat available to turtles in these areas. 

 These types of studies are of great importance in understanding 

 the habitat requirements of turtles in the pelagic environment. 

 Relative to remote sensing techniques, these types of small scale 

 vessel sampling surveys are inexpensive. 



Little work is being done in the offshore pelagic 

 environment. Concerns about the potential impact of plastics, 



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