ABSTRACT: Interpretation of diving profiles of aquatic animals would be considerably enhanced by additional behavioural information. A new sensor is presented here which records animal movements. This sensor was tested on a captive loggerhead turtle Caretta caretta which showed similar activity patterns to free-living green turtles Chelonia mydas. A computer program with user-selectable options was developed to analyse the data consistently and rapidly. Using our sensor we calculated the total resting time, which differed by less than 5% from the real resting time when the sampling interval was 2 s. The method was additionally tested for different sampling intervals to find out its applicability for field studies.

KEY WORDS: Activity sensor · Sea turtles · At-sea activity · Dive profiles · 3-D compass

Published in MEPS Vol. 185 (1999) on August 20
ISSN: 0171-8630. Copyright © Inter-Research, Oldendorf/Luhe, 1999