Management Research Needs 



Monitoring Nesting Beaches (Thomas A. Murphy and 

 Sally Hopkins-Murphy) 



Introduction 



The basic methodology for conducting aerial and ground 

 surveys of nesting beaches is contained in "The WATS Manual of 

 Sea Turtle Research and Conservation Techniques." This paper 

 will augment that chapter since more detailed information has 

 been gained since the manual was published. Much of this 

 information is based on 11 years of ground surveys, 8 years of 

 aerial surveys and 10 years of telemetric monitoring of 

 loggerheads, principally in the state of South Carolina, U.S.A. 



Monitoring of beaches will be divided into four survey 

 types. These include: (1) ground surveys conducted to tag 

 nesting turtles, (2) ground surveys to record turtle tracks on 

 the beach, (3) surveys conducted to document hatching success, 

 and (4) aerial surveys of turtle tracks. 



Tagging Nesting Turtles 



The most traditional beach monitoring has involved the 

 tagging of nesting turtles on the beach. Such surveys provide 

 information on nesting effort and allow the calculation of 

 statistical estimates of a variety of reproductive attributes. 

 The number of nests laid by an individual female per season, the 

 internesting interval, nest site fidelity, as well as 

 recruitment, survivorship and remigration intervals are such 

 attributes. The accuracy of these statistical estimates are 

 greatly influenced by survey efficiency, size of the survey area, 

 seasonal coverage, tag loss, number of survey years, methods used 

 and consistency of data collection. All tagging studies need to 

 be carefully documented and as standardized as possible. After 

 decades of monitoring, many of these statistical estimates need 

 verification using alternate methods such as telemetry. 



For example, the number of nests per season for loggerheads 

 is frequently reported between 1.9 and 2.1. This is a minimum 

 number and is related to survey efficiency, size of the study 

 area and the mean distance between nest sites of an individual 

 female. If nesting turtles are missed by survey personnel, if 

 all nights are not surveyed, if the entire nesting season is not 

 monitored or if the size of the study area is too small, the 

 number of nests per female will be underestimated. Except for a 

 few surveys of very isolated islands, there is always an edge 

 effect. This effect is a result of turtles which nest perhaps 



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