Using Ultrasonic Telemetry to Determine Home Range of a Coral-Reef Fish

Abstract

Recent advances in telemetry allow the tracking of larger numbers of individu- als over longer periods of time to reveal information about home range, spawning distribution, movement patterns, and habitat preference. Identifying and defining specific research objectives and parameters prior to initiating a telemetry study is critical. This paper outlines a series of topics that, when an- swered systematically, will assist in identifying a telemetry system appropriate to investigate and determine the home range of a coral-reef fish. An investi- gation of the home range of Nassau grouper (Epinephelus striatus) in the Ba- hamas is presented as a case study with points considered important to the suc- cess of the study. The materials and methods section directly applies elements of the case study. Results include a summary of the twenty two adult (>40 cm TL) Nassau grouper tracked by a radio-linked acoustic positioning buoy sys- tem. Mean number of position fixes was 3420 ± 1795 (SE) per fish ranging from 1032-7493. Data were analyzed using the Animal Movement Analysis Extension for Arcview®. Total cumulative home range increased less than 2% daily on tracking days 14-18 and less than I % daily on tracking days 18- 21. The mean home range area as determined by 95% minimum convex poly- gon (MCP) method for the Nassau grouper was 18305 m2 ± 5806 (SE); the smallest home range was 1565 m2 and the largest was 131805 m2•