Feeding behavior and visual field differences in loggerhead and leatherback sea turtles may explain differences in longline fisheries interactions

N Warraich,N Blume,J Wyneken

doi:10.3354/esr01012

Abstract

Feeding behavior and visual field differences in loggerhead and leatherback sea turtles may explain differences in longline fisheries interactions

Highlights

Fisheries bycatch is a significant source of mortality for sea turtles, sharks, seabirds, and other nontarget species worldwide (Lewison et al 2004a, Wallace et al 2013)
Mortality from longline bycatch is implicated in the decline of several sea turtle species in the Atlantic and Pacific Oceans (Spotila et al 2000, Piovano et al 2004, Lewison & Crowder 2007, Wallace et al 2013, Fossette et al 2014)
Bycatch of sea turtles may be rare for individual fishers, the cumulative numbers of hooks deployed can have a substantial impact on the population (Lewison et al 2004b, Coelho et al 2015)

Summary

Introduction

Fisheries bycatch is a significant source of mortality for sea turtles, sharks, seabirds, and other nontarget species worldwide (Lewison et al 2004a, Wallace et al 2013). Loggerhead Caretta caretta and leatherback Dermochelys coriacea sea turtles are caught incidentally on longlines (Lewison et al 2004a, Watson et al 2005, Foster et al 2012) These individuals are often large immature or adult animals that represent future recruitment to the reproductive segment of populations (Wallace et al 2008). Effects of hookings can range from slight injury, to delayed mortality following release, to death on the line Such direct and delayed losses negatively impact population recovery (Lewison et al 2004a, Donoso & Dutton 2010, Alfaro-Shigueto et al 2011, Swimmer et al 2012)

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