Ontogenetic movements of juvenile blacktip reef sharks: evidence of dispersal and connectivity between coastal habitats and coral reefs

Abstract

ABSTRACTConnectivity between coastal habitats and mid‐shelf and offshore coral reefs is a topical issue in the conservation and management of fishes and coastal ecosystems.Coastal habitats provide a range of ecosystem functions for sharks and rays and the use of coastal ecosystems by these species affects conservation and management outcomes. There is a growing need to better understand movement and habitat use patterns given recorded declines of many shark and ray species around the world.This study presents evidence of connectivity of blacktip reef sharks between coastal and offshore habitats, with juveniles dispersing from natal grounds at the onset of maturity and moving to new locations including offshore coral reefs.These dispersal patterns differ from previous accounts of reef shark movements and provide new evidence of connectivity among coastal habitats and offshore coral reefs.These large‐scale movements may help to maintain genetic diversity of populations, and could increase the resilience of blacktip reef shark populations to localized pressures. These movement and connectivity patterns also illustrate the potential importance of coastal habitats to reef shark conservation. Copyright © 2013 John Wiley & Sons, Ltd.