Byles, Richard 



Development of a Sea Turtle Satellite Bioteleroetry System 



U.S. Fish and Wildlife Service 

 Albuquerque, New Mexico 87103 USA 



A location and data gathering system has been developed for 

 use with free-ranging sea turtles utilizing System Argos. 

 Previous satellite tracking experiments were basically limited to 

 locations of individual turtles. The present system transmits a 

 record of the number and mean duration of dives over the prior 

 twelve hours, the duration of the last dive and the current sea 

 water temperature. Prototype transmitters have been deployed on 

 loggerhead (Caretta caretta) sea turtles in the western mid- 

 Atlantic and Kemp's ridley ( Lepidochelys kempi ) sea turtles in 

 the Gulf of Mexico. Locations for an individual turtle are 

 obtained from System Argos on an average of only every eight to 

 ten days due to mismatches between the turtle's surface and 

 submergence cycle and satellite passes. However, data are 

 usually obtained on a daily basis from surface transmissions of 

 insufficient duration for location calculations. Preliminary 

 data from two ridleys indicate submergences from less than one 

 minute to eight hours, with an average of 32.2 minutes, (std. 

 dev. 34.6, n = 71). Four loggerheads in the Chesapeake Bay and 

 Mid-Atlantic Bight were telemetered with earlier versions of the 

 PTT that did not sample submergence times. Two of these 

 transmitters were detached from the animals after limited 

 migration tracking and became drift buoys, tracking currents and 

 temperatures. The attachment system is currently being refined 

 and the housing is being re-designed for use with various species 

 of sea turtles. A depth sensor is currently being tested with 

 the PTT to add mean and maximum depths to the data stream. 

 Another loggerhead from Chesapeake Bay and a black turtle 

 (Chelonia acfassizii ) from Pacific Mexico will be telemetered in 

 the late summer and fall of 1987. Twenty L. kempi will be 

 telemetered with transmitters during the 1988 nesting season and 

 monitored throughout an annual cycle. 



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