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Postlarval Growth and Reproductive Biology of the Xanthid Crab, Neopanopetexana Sayi

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Postlarval Growth and Reproductive Biology of the Xanthid Crab, Neopanopetexana Sayi W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 1972 Postlarval growth and reproductive biology of the xanthid crab, neopanopetexana sayi Richard Carlyle Swartz College of William and Mary - Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Marine Biology Commons Recommended Citation Swartz, Richard Carlyle, "Postlarval growth and reproductive biology of the xanthid crab, neopanopetexana sayi" (1972). Dissertations, Theses, and Masters Projects. Paper 1539616870. https://dx.doi.org/doi:10.25773/v5-v6hh-sb54 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. 72-17,317 SWARTZ, Richard Carlyle, 1943- POSTLARVAL GROWTH AND REPRODUCTIVE BIOLOGY OF THE XANTHID CRAB, NEOPANOPE TEXANA SAYI. The College of William and Mary in Virginia, Ph.D., 1972 Marine Sciences University Microfilms, A XEROX Com pany, Ann Arbor, Michigan © 1972 Richard Carlyle Swartz ALL RIGHTS RESERVED Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. POSTLARVAL GROWTH AND REPRODUCTIVE BIOLOGY OF THE XANTHID CRAB, NEOPANOPE TEXANA SAYI A Dissertation Presented To The Faculty of the School of Marine Science The College of William and Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Doctor of Philosophy By Richard Carlyle Swartz 1972 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPROVAL SHEET This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Richard C. Swartz c7 Approved, January 1972 Willard A. Van Engel, PhCwT S ' ^ —n/ A—// y — ^ J. Hargis7, Jf., Ph.D. /J t A. Musick, Ph.D. C? / Dexter S. Haven, M.S. C. Richard Terman, Ph.D. Department of Biology Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. PLEASE NOTE: Some pages may have indistinct print. Filmed as received. University Microfilms, A Xerox Education Company Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Page ACKNOWLEDGMENTS....................... iv LIST OF T A B L E S ....................................... v LIST OF FIGURES....................................... vii ABSTRACT .............................................. xii INTRODUCTION .......................................... 1 GENERAL MATERIALS AND METHODS .......................... 5 RESULTS................................................ 1 1 I - SEASONAL CYCLES OF GROWTH AND REPRODUCTION .... 11 Temperature, Salinity, and Photoperiod Cycles . 1 1 The Molting Season .............................. 1 4 The Winter Anecdysis ............................ 22 The Seasonal Reproductive Cycle ................ 35 Initiation of Spawning and Molting in the Spring . 4 4 Size-Frequency Analysis ........................ 55 II - REPRODUCTIVE BIOLOGY...................... 63 Social Behavior ................................ 63 Copulation...................................... 79 Spawning........................................ 86 Sexual Dimorphism and Maturity .................. 100 III - THE MOLT C Y C L E ............................. 115 Molting Behavior ................................ 115 Size Increment and Intermolt Duration .......... 123 Regulation of the Molt C y c l e .................... 128 S a l i n i t y .................................... 128 L i g h t ........................................ 131 Background Color ............................ 1 3 4 Food Requirements............................ 136 A u t o t o m y .................................... 1 4 4 Eyestalk Ablation ............................ 1 6 4 DISCUSSION ............................................ 167 LITERATURE CITED ...................................... 214 VITA .................................................. 230 iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS I am most grateful to Mr. Willard Van Engel who provided guidance throughout this study. I also thank Dr. John Musick and my wife Patricia who critically reviewed the manuscript, Mrs. Jane Davis, Mrs. Kay Stubblefield, and Mr. Kenneth Thornberry who prepared the figures, Mr. Roy Terretta and Dr. George Marsh who aided in photography, Mr. Frank Wojick who prepared the computer programs used in the statistical analyses, and Dr. Mark Chittenden who suggested the use of the Student-Newman-Keul’s multiple range test. Mrs. Jacqueline Norcross kindly translated portions of several French publications. Miss Susan Barrick and her staff were most helpful in obtaining references. Messrs. Thomas Chapman and Hayes Bolden spent a great deal of effort on the maintenance of the temporary laboratory facility in which this research was conducted. Mrs. Ruthella Rozier typed the manuscript and made many helpful suggestions during its preparation. During the period of this study I was supported by a National Science Foundation Cooperative Traineeship. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Table Page 1. Duration of the molting season in the Neopanope population in the York River at Gloucester Point . 15 2. Seasonal distribution of molts recorded in the Monthly Molt Study, in relation to temperature .... 17 3. Size distribution of the specimens in the July - October 1969 Monthly Molt s a m p l e s .................. 18 4. The time intervals from A T to the first molt and from the first to the second molt of the Warm and Cold groups of the A T ex p e r i m e n t .................. 26 5. Mortality within seven groups of five crabs, which were brought from ambient temperature to room tem­ perature, autotomized, and, at various times after autotomy, returned to ambient temperature .......... 32 6 . Size increment at ecdysis and A T - Molt I inter­ val of whole crabs and specimens whose eyes were a b l a t e d ............................................ 34 7. The number of ovigerous females among crabs > 6.0 mm in 28 collections made between 1 May 1969 and 18 November 1970 ................................ 38 8 . The seasonal distribution of copulations observed in community tanks in the laboratory................ 40 9. The condition of ovarian eggs and spermathecae in mature females collected during the winter anecdy- sis of 1969-1970 .................................... 42 10. The history of 100 crabs collected during their winter anecdyses on 1 May 1970 and held in a community tank until they molted, spawned, died or escaped.......................................... 49 11. Size distribution of mature females which spawned before molting at the end of the winter anecdysis, as opposed to those which molted without spawning f i r s t .............................................. 51 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Table Page 12. The molt-spawn history of 32 females which spawned at least once before molting at the end of the 1969-1970 winter anecdysis .......................... 53 13. The size distribution of immature and mature Neopanope females in collections made during the molting season and winter anecdysis of 1970 59 14. Sex ratio in relation to carapace width of Neopanope specimens in the Total Collections .................. 61 15. Duration of copulation stages in Neopanope .......... 78 16. The frequency of copulation by individual Neopanope in the spring before the end of the winter anecdysis . 84 17. Temporal relationships between molting, spawning, and hatching in mature Neopanope females ............ 87 18. The relationship between ambient temperature and brooding time of Neopanope.......................... 89 19. Effect of the presence of males on the postmolt spawning history of Neopanope females .............. 90 20. Changes in the external morphology of Neopanope females at the pubertal m o l t .......................... 1 1 2 21. Intermolt duration and size increment at ecdysis of Neopanope juveniles held at different salinities . 130 22. Intermolt duration of Neopanope juveniles subjected to different photoperiods ................ 133 23. Intermolt duration of Neopanope juveniles exposed to different background colors ...................... 1 35 24. Intermolt duration, size increment, and survival of Neopanope juveniles maintained on different feeding schedules .................................. 140 25. The survival and A T - ecdysis duration of starved Neopanope juveniles.which were either subjected to dual cheliped autotomy or left i n t a c t ................ 143 26. Regeneration fate and A T - ecdysis duration of Neopanope juveniles in relation to the time of dual cheliped autotomy .............................. 147 27. Intermolt duration of Neopanope juveniles subjected to dual cheliped autotomy on the day of ecdysis, relative to those not autotomized .................. 150 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Table Page 28. Regeneration fate and intermolt duration of Neopanope juveniles as a function of the time between left
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