Spatial ecology of juvenile lemon sharks Emphasi

Authors: Karen J Murchie Emily Schwager Steven J Cooke Andy J Danylchuk Sascha E Danylchuk Tony L Goldberg Cory D Suski David P Philipp

Publish Date: 2010/07/07

Volume: 89, Issue: 1, Pages: 95-104

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Abstract

Fisheries exploitation and habitat alteration are threatening lemon shark Negaprion bevirostris populations because they use nearshore regions as nursery sites As such there is a need for information on the spatial ecology of juvenile lemon sharks to identify critical habitats that require protection as well as to understand their basic ecology The purpose of this study was to determine the habitat preferences and movement patterns of juvenile lemon sharks along a subsection of coastline characterized by coastal flats and tidal creeks of Eleuthera The Bahamas Eleven juvenile lemon sharks 766 ± 127 mm total length mean±SD were captured from various tidal creeks within the 23 km study area and were surgically implanted with acoustic transmitters A series of 27 hydrophone receivers acted as a passive monitoring array to detect tagged individuals as they moved among habitats Findings suggest that juvenile lemon sharks tagged in this study prefer shallow water habitats within tidal creeks and typically display high site fidelity with occasional forays to alternate habitats or creeks In fact more than 90 of tagged lemon sharks had the greatest percentage of detections located at a receiver at or close to the location where they were tagged There was no evidence of differences in diel or seasonal movement and habitat use Knowledge gained from this study will be useful for directing future conservation and management strategies including coastal development plans and marine protected areasWe gratefully acknowledge C Maxey and the staff students and volunteers of the Cape Eleuthera Institute and The Island School for logistical support and assistance with field work In particular A Schultz E Brooks A Oronti S Langosch and T Voorhees We also thank other research staff including J Koppelman J Claussen M Philipp and M Philipp This project was supported by a grant from the Charles A and Anne Morrow Lindbergh Foundation Additional financial support was provided by the Canadian Foundation for Innovation the Ontario Research Fund Carleton University the Cape Eleuthera Foundation Bonefish Tarpon Unlimited and the University of Illinois K Murchie was supported by a Natural Sciences and Engineering Research Council CGSD fellowship We also thank The Bahamas Department of Marine Resources for their support

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