LIFE HISTORY, ECOLOGY AND CONSERVATION OF EUROPEAN SEAHORSES Janelle Marie Renelle Curtis Department of Biology McGill University Montréal Québec August 2004 "Who knows what admirable virtue offishes may be below low-water-mark, bearing up against a hard destiny, not admired by that fellow creature who alone can appreciate if!" Henry David Thoreau A thesis submitted to McGill University in partial fulfillment ofthe requirements of the degree of Doctor of Philosophy © Janelle Marie Renelle Curtis 2004 Library and Bibliothèque et 1+1 Archives Canada Archives Canada Published Heritage Direction du Branch Patrimoine de l'édition 395 Wellington Street 395, rue Wellington Ottawa ON K1A ON4 Ottawa ON K1A ON4 Canada Canada Your file Votre référence ISBN: 0-494-12826-7 Our file Notre référence ISBN: 0-494-12826-7 NOTICE: AVIS: The author has granted a non­ L'auteur a accordé une licence non exclusive exclusive license allowing Library permettant à la Bibliothèque et Archives and Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par télécommunication ou par l'Internet, prêter, telecommunication or on the Internet, distribuer et vendre des thèses partout dans loan, distribute and sell th es es le monde, à des fins commerciales ou autres, worldwide, for commercial or non­ sur support microforme, papier, électronique commercial purposes, in microform, et/ou autres formats. paper, electronic and/or any other formats. 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While these forms may be included Bien que ces formulaires in the document page count, aient inclus dans la pagination, their removal does not represent il n'y aura aucun contenu manquant. any loss of content from the thesis. ••• Canada TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................................. 11 LIST OF TABLES ....................................................................................................................................... V LIST OF FIGURES ................................................................................................................................ VIII PREFACE .................................................................................................................................................. Xll THESIS FORMAT AND STYLE ..................................................................................................................... XII CONTRIBUTION OF CO-AUTHORS ............................................................................................................. XIV ORIGINAL CONTRIBUTIONS TO KNOWLEDGE .. , ........................................................................................ XV T AXONOMIC CLARIFICATION ................................................................................................................... XVI ACKNOWLEDGEMENTS ........................................................................................................................... XVII THESIS ABSTRACT .................................................................................................................................... 1 RÉSUMÉ ........................................................................................................................................................ 2 GENERAL INTRODUCTION .................................................................................................................... 3 THE THREATENED STATUS OF MARINE FISHES ............................................................................................. 3 FACTORS THAT CONFER RISK ............. '" ..................................................................................................... .4 RISK ASSESSMENTS FOR MARINE FISHES ...................................................................................................... 6 THE THREATENED STATUS OF SEAHORSES ................................................................................................... 9 SUMMARY OF RESEARCH OBJECTIVES ....................................................................................................... 10 LITERATURE CITED .................................................................................................................................... 12 LINKING STATEMENT 1 ........................................................................................................................ 20 CHAPTER 1 ................................................................................................................................................ 21 LIFE HISTORY OF AN UNUSUAL MARINE FISH: SURVIVAL, GROWTH AND MOVEMENT PATTERNS OF THE EUROPEAN LONG-SNOUTED SEAHORSE, HIPPOCAMPUS GUTTULATUS (CUVIER 1829) ABSTRACT ................................................................................................................................................. 22 INTRODUCTION .......................................................................................................................................... 23 MATERIALS AND METHODS ....................................................................................................................... 24 Species description .............................................................................................................................. 24 Site characteristics .............................................................................................................................. 25 Measuring seahorses ........................................................................................................................... 26 Mark-recapture study .......................................................................................................................... 26 Experimental fishing ............................................................................................................................ 28 Home range size and movement patterns ............................................................................................ 28 Growth ................................................................................................................................................. 29 Survival, generation lime and longevity .............................................................................................. 31 RESULTS ................................................................................................................................................... 33 Population structure ............................................................................................................................ 33 Home range size and movement patterns ............................................................................................ 34 Growth ................................................................................................................................................. 35 Survival, generation time and longevity .............................................................................................. 37 DISCUSSION .............................................................................................................................................. 38 Population structure ............................................................................................................................ 38 Home range size and movement patterns ............................................................................................ 38 Growth ................................................................................................................................................. 40 Survival and longevity ......................................................................................................................... 41 Life history strategy ............................................................................................................................. 42 IMPLICATIONS FOR MANAGEMENT AND CONSERVATION .......................................................................... .43 11 CONCLUSIONS ........................................................................................................................................... 45 LITERATURE CITED .................................................................................................................................... 46 LINKING STATEMENT 2 ........................................................................................................................ 66 CHAPTER2 ................................................................................................................................................ 67 ESTIMATING REALIZED ANNUAL FECUNDITY IN A BROODING