W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 1975 Food Habits of Some Demersal Fishes of the Continental Slope and Rise George R. Sedberry College of William and Mary - Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Fresh Water Studies Commons, Marine Biology Commons, Oceanography Commons, and the Zoology Commons Recommended Citation Sedberry, George R., "Food Habits of Some Demersal Fishes of the Continental Slope and Rise" (1975). Dissertations, Theses, and Masters Projects. Paper 1539617460. https://dx.doi.org/doi:10.25773/v5-mj9w-zx56 This Thesis 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]. FOOD HABITS OF SOME DEMERSAL FISHES OF THE CONTINENTAL SLOPE AND RISE A Thesis 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 Master of Arts / >-*t tf?« ^ * .•'♦vrunjA !n*>TfT±ej:'i \ v of i '■ , .*AP;r:.r J by '---- George R. Sedberry, III 1975 APPROVAL SHEET This thesis is submitted in partial fulfillment of the requirements for the degree of Master of Arts George R. S&dberry, Approved, August 1975 G- „Jonn A. fMsick Paul A. HaefnerC Jr / 9 , Gfeorge Cx Grant Donald F. Boesch . Merriner ii TABLE OF CONTENTS Page ACKNOWLEDGMENTS........................................... iv LIST OF T A B L E S ....................... vi LIST OF FIGURES..................................... vli ABSTRACT................................................... viii INTRODUCTION .............................................. 2 METHODS AND MATERIALS..................................... 5 RESULTS AND DISCUSSION ................................... 10 CONCLUSIONS................................................ 52 APPENDIX.................................................. 58 LITERATURE CITED ......................................... 61 ili ACKNOWLEDGMENTS I thank Dr. John A. Musick, chairman of my thesis committee, for suggesting this problem, and for his suggestions and criticisms. I also thank members of my committee, Drs. P. A. Haefner, Jr., G. C. Grant, D. F. Boesch, and J. V. Merriner, for their criticisms and review of the manuscript. For their help in identifying food items, I thank Dr. Clyde F. E. Roper of the U. S. National Museum of Natural History, who identified some of the cephalopod beaks; Dr. E. L. Bousefield of the National Museum of Canada, who identified many of the amphipods and gave me information on their distribution; and John E. Olney and Dr. G. C. Grant of the Virginia Institute of Marine Science (VIMS), who identified many of the copepods. Dr. P. A. Haefner, Jr. introduced me to the literature on crustaceans and gave me access to his library, and Elizabeth G. Lewis of VIMS identified some of the decapods. Ship time and financial support were provided by National Science Foundation (NSF) Grants GD-32560, CG-00005 (Cruises E-l-73 and E-2-74 respectively), NSF grant GA-37561 (Cruises CI-73-10 and GI-74-04 respectively), and Sea Grant 04-4-1-158-31 (Cruise D-2-74). For sharing their knowledge and suggestions with me, I thank my fellow graduate students, especially Douglas Markle and Labbish Chao. Special thanks are extended to Charles Wenner, who spent many hours cutting out stomachs and recording data for me, and who also gave me many helpful suggestions. A special thanks is extended to my wife, Joan, for typing an earlier draft of the manuscript, for her material and moral support, and for her patience and encouragement throughout the duration of this study. v LIST OF TABLES Table Page 1. List of fishes examined........................... 5 2. Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Synaphobranchus kaupi....................................... 13 3. Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Halosauropsis macrochir................................... 22 4. Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Aldrovandia spp. ................................. 29 5. Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Phycis chesteri . 35 6 . Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Lycodes atlanticus................................ 43 7. Percent frequency occurrence, percent numerical dominance, percent volume displacement, and index of relative importance of food items in the stomachs of Coryphaenoides armatus..................................... 48 vi LIST OF FIGURES age Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance for higher taxonomic groups of food in the diet of Synaphobranchus kaupi............... 15 Percent frequency occurrence of pelagic fishes in stomachs of Synaphobranchus kaupi in relation to time of day of collection . 19 Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance for higher taxonomic groups of food in the diet of Halosauropsis macrochir............. 24 Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance for higher taxonomic groups of food in the diet of Aldrovandia spp...................... 28 Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance for higher taxonomic groups of food in the diet of Phycis chesteri...................... 38 Percent frequency occurrence of pelagic fishes and euphausiids in the stomachs of Phycis chesteri in relation to time of day of collection................... 41 Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance of higher taxonomic groups of food in the diet of Lycodes atlanticus................. 45 Percent frequency occurrence, percent number, percent volume displacement, and index of relative importance of higher taxonomic groups of food in the diet of Coryphaenoides armatus ............. 50 vii ABSTRACT Stomach contents of 742 fishes comprising 14 species were examined from the continental slope and rise of the Middle Atlantic Bight. Analysis of the stomachs show two main types of feeders among benthic deep-sea fishes: those that feed primarily on pelagic food items, and those that feed by rooting in the sediments, ingesting infauna1 and epifaunal invertebrates. The diets of both pelagic and benthic feeders are found to be unspecialized. This suggests the benthic feeders may play a role in maintaining the high species diversity found in benthic invertebrates, as Dayton and Hessler (1972) have hypothesized. v• m• • FOOD HABITS OF SOME DEMERSAL FISHES OF THE CONTINENTAL SLOPE AND RISE INTRODUCTION Little is known of the food of demersal fishes of the continental slope and rise and of the abyss (Marshall, 1965 Bright, 1970; Grassle and Sanders, 1973). Thus, on other than a theoretical basis, relatively few studies have dealt with trophic structure in the deep sea. Marshall (1954) reported the food of some deep living invertebrates and fishes and reviewed the two main theories of food provision to the deep sea: the rain of dead plankton (Agassiz, 1888) and vertically migrating food chains (Vinogradov, 1953 as cited by Vinogradov, 1962). Vinogradov (1962), on the basis of feeding patterns among the deep-sea zooplankton, proposed that overlapping vertical migrations were the most likely mechanism of food transport from the productive surface waters down to great depths. Menzies (1962) again reviewed the theories of food sources and proposed the rain of dead plankton as the most important food source on the basis of his observations of isopods and the literature. Studies related to the mechanism of food transport and the food of deep-sea invertebrates have been reported by Krogh (1934), Sokolova (1957,1959), Barnard (1962), Isaacs (1969) Sanders and Hessler (1969), Harding (1973), Dayton and Hessler (1972), Grassle and Sanders (1973), and others (see Zenkevich and Birstein, 1956 for earlier studies). 3 Food of deep-sea pelagic fishes has received some attention in recent years (Marshall, 1954; Haedrich, 1964; Haedrich and Nielson, 1966; Duka, 1969; Collard, 1970; Childress and Meek, 1973; and others; see Merrett and Roe, 1974 for review), but less information is available for benthic and benthopelagic fishes. Stomach contents of some species have been reported cursorily in taxonomic and other works (Bigelow and Schroeder, 1953; Marshall, 1954; Cohen, 1958; Nielson, 1964; Marshall, 1965; Bright, 1968; Robins, 1968; Marshall and Iwamoto, 1973; McDowell, 1973). Bright (1970) examined the stomachs of many species of deep-sea fish from the Gulf of Mexico and constructed a food web based on data from 81 small specimens. Clarke and Merrett (1972) discussed the significance of pelagic food in