Attaching a sonic tag to the carapace improves the line-of -sight 

 tracking capabilities but requires the use of a directional 

 hydrophone submerged from a vessel. The ability to track a 

 turtle using an acoustic device is dependent upon the amount of 

 ambient noise. In the Cape Canaveral area, constant ship noise 

 reduced the effective detection range to 100 yards (A. Kemmerer, 

 pers. comm. ) . 



A second tracking experiment targeting headstarted Kemp's 

 ridley turtles was conducted in both Florida Bay and off 

 Homosassa, Florida, on the Florida west coast. The tracking 

 transmitter was housed in a pyramidal float to minimize drag 

 (Timko and DeBlanc 1981) . Before turtles were released, behavior 

 studies were completed to insure that behavior was not affected 

 by the presence of the transmitter. Turtles were tracked up to 

 30 days and turtles moved as much as 150 miles from the release 

 point (Timko and DeBlanc 1981) . 



The ability to obtain information on sea surface time is 

 important in describing the behavior of turtles in the pelagic 

 environment. These data can be used to correct aerial survey 

 counts and therefore absolute abundance, rather than relative 

 abundance, can be estimated. The short range movements of 

 turtles can be defined to provide basic biological information on 

 pelagic activities of turtles such as habitat utilization and 

 residence time. 



Satellite tracking remote sensing ; The only way to derive 

 direct information on long range movements and migration patterns 

 is through the use of satellite tracking technology. This 

 information can provide insights into population ranges and 

 limits. Thus, the boundaries of a unit stock and migratory 

 routes may ultimately be defined if adequate sample sizes are 

 achieved. 



The NMFS/SEFC has been involved with this technology since 

 1979. The first satellite utilized to track turtles was the 

 NIMBUS system. This system was designed to collect 

 meteorological and oceanographic data from randomly located 

 mobile transmitters. Position of a signal was estimated within 

 five kilometers of the transmitter. A cylindrical transmitter 

 was attached to a loggerhead nicknamed "Dianne" that was obtained 

 from a Mississippi shrimp boat (Timko and Kolz 1982) . This 

 turtle was released offshore and both visual and radio contact 

 was immediately lost. Satellite transmissions were received over 

 an eight month period from October 1979 to June 1980. During 

 this period the turtle was tracked from Louisiana south and west 

 to Corpus Christi and back to the Texas-Louisiana border before 

 the transmitter was located in Kansas. Apparently the 

 transmitter was found on a Texas beach and taken to a home in 

 Kansas which was located via satellite transmission. The total 

 tracking distance exceeded 1,400 miles (Timko and Kolz 1982). 



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