Southeast Florida reef fish abundance and biology: Five year performance report Luiz R. Barbieri and James A. Colvocoresses SEDAR51-RD-20 November 2016 FIVE-YEAR PERFORMANCE REPORT TO THE U.S. DEPARTMENT OF INTERIOR FISH AND WILDLIFE SERVICE FROM THE FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION FLORIDA MARINE RESEARCH INSTITUTE SOUTHEAST FLORIDA REEF FISH ABUNDANCE AND BIOLOGY GRANT F-73 FUNDED BY THE FEDERAL AID IN SPORT FISH RESTORATION ACT JUNE 2003 - FWC\FMRI File Code: F0628-2221-97-02-F STATE: FLORIDA GRANT NUMBER: F-73 GRANT TITLE: SOUTHEAST FLORIDA REEF FISH ABUNDANCE AND BIOLOGY GRANT DATES: APRIL 1ST, 1997 THROUGH JUNE 30TH, 2002 PRINCIPAL INVESTIGATORS: LUIZ R. BARBIERI AND JAMES A. COLVOCORESSES PREPARATION DATE: JUNE 2003 - PREFACE SOUTHEAST FLORIDA REEF FISH ABUNDANCE AND BIOLOGY This is an interim report on the first five years of an ongoing study of the biology, life history, and population dynamics of important reef fish in southeast Florida. This first phase of the grant included studies that focused on yellowtail snapper (Ocyurus chrysurus), gray snapper (Lutjanus griseus), mutton snapper (L. analis) and lane snapper (L. synagris), all of which support important recreational (as well as commercial) reef fisheries in Florida. Studies on other species will be initiated in the future as additional species important to recreational reef fisheries in Florida are identified. Results presented in this report include manuscripts that have already been published as well as unpublished reports that address various project components (i.e., age and growth, reproduction, feeding habits, etc.). This report is organized in three main Sections: Section I includes the preliminary results of the study on age, growth, and reproduction of the four targeted snappers species listed above. Section II includes two separate studies on the feeding ecology of these same snapper species. Section III presents the results of the artificial reef monitoring program conducted in cooperation with Palm Beach County’s Department of Environmental Resources Management. This work was supported in part under funding from the Department of the Interior, U.S. Fish and Wildlife Service, Federal Aid for Sport Fish Restoration Grant Number F-73. - 1 - - TABLE OF CONTENTS SECTION I – LIFE HISTORY........................................................................................... 4 Age, Growth, and Reproduction of Snappers in Southeast Florida............................ 4 Introduction............................................................................................................. 4 Methods................................................................................................................... 5 Study Area .................................................................................................. 5 Collection Methods................................................................................... 10 Laboratory Processing .............................................................................. 15 Otolith Removal and Storage.................................................................... 17 Otolith Sectioning and Mounting.............................................................. 17 Age Assignment........................................................................................ 19 Age Validation.......................................................................................... 21 Aging Precision......................................................................................... 21 Length and Weight Relationships............................................................. 21 Growth Estimates...................................................................................... 22 Mortality Estimates................................................................................... 22 Results................................................................................................................... 23 Numbers and Sizes of Fish Sampled ........................................................ 23 Age Determination.................................................................................... 28 Growth ...................................................................................................... 28 Maturity and Spawning............................................................................. 50 Literature Cited ..................................................................................................... 50 SECTION II – FEEDING ECOLOGY............................................................................. 62 Feeding Ecology of Four Species of Snappers ........................................................ 62 Introduction........................................................................................................... 62 Objectives ............................................................................................................. 63 Methods................................................................................................................. 63 Chevron traps............................................................................................ 63 Hook-and-line gears.................................................................................. 64 - 2 - - Spearfishing .............................................................................................. 65 Sample handling........................................................................................ 65 Data management...................................................................................... 65 Results................................................................................................................... 65 Discussion............................................................................................................. 68 References............................................................................................................. 69 Predation on Loggerhead and Leatherback Post-Hatchlings by Gray Snapper........ 80 SECTION III – ARTIFICIAL REEF MONITORING..................................................... 86 Comparison of artificial and natural reefs off southeast Florida .............................. 86 Abstract................................................................................................................. 86 Introduction........................................................................................................... 87 Materials and Methods.......................................................................................... 88 Description of monitoring sites................................................................. 88 Survey Methods ........................................................................................ 89 Data analyses ............................................................................................ 89 Results................................................................................................................... 91 Overall assemblage structure .................................................................... 91 Comparisons among artificial reefs .......................................................... 91 Comparisons among natural reefs (March 2000 – March 2001) .............. 92 Comparisons between artificial and natural reefs..................................... 92 Life-stage data........................................................................................... 93 Discussion............................................................................................................. 93 Abundances of economically important species....................................... 93 Juvenile abundance ................................................................................... 94 Assemblage structure................................................................................ 95 Artificial Reef Colonization...................................................................... 96 Acknowledgements............................................................................................... 97 Literature Cited ..................................................................................................... 98 - 3 - - SECTION I – LIFE HISTORY AGE, GROWTH AND REPRODUCTION OF RECREATIONALLY IMPORTANT SNAPPERS IN SOUTHEAST FLORIDA Luiz R. Barbieri1, Erick R. Ault2, James G. Knapp2 , Erin E. McDevitt2, and Paul E. Thomas2 1Florida Fish & Wildlife Conservation Commission, Florida Marine Research Institute 100 Eighth Avenue SE, St. Petersburg, FL 33701-5095 2Florida Fish & Wildlife Conservation Commission, Florida Marine Research Institute, Tequesta Field Laboratory 19100 SE Federal Highway, Tequesta, FL 33469 INTRODUCTION Reef fishes of the snapper-grouper complex are among the most important commercial and recreational fisheries resources of the southeastern United States. This fish community consists of demersal tropical and subtropical species which generally occupy true coral reefs as well as “live-bottom” habitats and are caught by common fishing methods on continental shelf waters. Although the 1983 South Atlantic Fishery Management Council’s snapper-grouper fishery management plan includes a total of 8 families, snappers (family Lutjanidae) and groupers (family Serranidae) are the most important in terms of number of species, desirability as food and sport fishes as well as in magnitude of catches. Along the