MOLLUSCAN INTRODUCTIONS AND TRANSFERS A Maryland Sea Grant Publication College Park Maryland MOLLUSCAN INTRODUCTIONS AND TRANSFERS MOLLUSCAN INTRODUCTIONS AND TRANSFERS Rrsx CoNSIDERATIONs AND IMPLICATIONS A Symposium Proceedings Edited by ] ames T. Carlton and Aaron Rosenfield ...,.~ . (.......-~j/4!1!!f~~ A Maryland Sea Grant Publication ·~ .. College Park, Maryland Published by the Maryland Sea Grant College, University of Maryland, College Park. Publication of this book is supported by grant #NA46RG009l from the National Oceanic and Atmospheric Administra­ tion to the Maryland Sea Grant College and by Grant #NA90AA-D-SG 184. The papers in this book were presented at a special symposium, Molluscan Introductions and Transfers: Risk Consider­ ations and Implications, presented at the 82nd Annual Meeting of the National Shellfisheries Association and the Shellfish Institute of North America, held April 4-5, 1990 in Williamsburg, Virginia. All the papers are reprinted with the permission of the Journal of Shellfish Research. Copyright © 1994 Maryland Sea Grant College. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, elec­ tronic or mechanical, including photocopying, recording, or any information storage or retrival system, without permis­ sion in writing from Maryland Sea Grant. Sea Grant is a federal-state-university partnership encouraging the wise stewardship of our marine resources through research, education and technology transfer. University of Maryland Publication UM-SG-TS-94-02 ISBN: 0-943676-58-4 For information on Maryland Sea Grant publications, contact: Maryland Sea Grant College 0112 Skinner Hall University of Maryland System College Park, Maryland 20742 Printed on recycled paper. Contents Contributors................................................................................................... ............................................................ vii james T. Carlton and Aaron Rosenfield Introduction to the special symposium on molluscan introductions and transfers: Risk considerations and implications .................................................................................................................................................. James T. Carlton Introduced marine and estuarine mollusks of North America; An end-of-the-20th-century perspective..... 3 Melbourne R. Carriker Introductions and transfers of mollusks: Risk considerations and implications .................... ...................... 21 Roger Mann, Eugene M. Bu"eson and Patrick K. Baker The decline of the Virginia oyster fishery in Chesapeake Bay: Considerations for introduction of a non-endemic species, Crassostrea gigas (Thunberg, 1793) ......................................................................... 25 Douglas W. Lipton, Eileen F. Lavan and Jvar E. Strand Economics of molluscan introductions and transfers: The Chesapeake Bay dilemma................................. 35 Cameron Ray Hackney, Marylin B. Kilgen, and Howard Kator Public health aspects of transferring mollusks.............................................................................................. 45 Patrick M. Gaffney and Standish K. Allen, Jr. Genetic aspects of introduction and transfer of molluscs.............................................................................. 59 Susan E. Ford Avoiding the transmission of disease in commercial culture of molluscs, with special reference to Perkinsus marinus ("Denno") and Haplosporidium nelsoni (MSX) ............................................................................. 63 NOTE: When referencing these papers, please cite the original source: Journal ofShcl(flsh Research. Volume, page numbers and year for each paper arc as follows: Carlton and Rosenfield, 11(2):487, 1992: Carlton, 11(2):489-505. 1992; Carriker, 11 (2):507-5 I 0, 1992: Mann, Burrcson and Baker, I 0(2)::179-3RR, 1991; Lipton, Lavan and Strand, 11 (2):511-519, 19n; Hackney, Kilgcn and Kat or, 11 (2):521-533, 1992; Gaffney and Allen, 11 (2):535-538, 1992; Ford, II (2):539-546, I 992. v Contributors Standish K. Allen, Jr. Howard Kator Haskin Shellfi.<.h Research Laboratory School of Marine Science Rutgers University Virginia Institute of Marine Science Port Norris. New Jersey 08349 College of William and Mary Glouce:.ter Point, Virginia 23062 Patrick K. Baker Virginia Institute of Marine Science Marylin B. Kilgen School of Marine Science Department of Biology College of William and Mary Nicholls State University Gloucester Point, Virginia 23062 Thibodaux, Louisiana 70310 Eugene M. Burreson Eileen F. Lavan Virginia Institute of Marine Science Marine Environmental and Estuarine Studies Program School of Marine Science University of Maryland College of William and Mary College Park, Maryland 20742 Gloucester Point, Virginia 23062 Dougla~· W. Lipton Melbourne R. Carriker Department of Agricultural and Resource Economics College of Marine Studies University of Maryland University of Delaware College Park, Maryland 20742 Lewes, Delaware Roger Mann James T. Carlton Virginia Institute of Marine Science Maritime Studies Program School of Marine Science Williams College-Mystic Seaport College of William and Mary 50 Greenmanville Avenue Gloucester Point, Virginia 23062 Mystic, Connecticut 06355 Aaron Rosenfield Susan E. Ford Northeast fisheries Science Center Haskin Shellfish Research Laboratory National Marine Fi:.heries Service Rutgers University Oxford, Maryland 21654 Port Norris, New Jersey 08349 lvar E. Strand Patrick M. Gaffney Department of Agricullural and Resource Economics College of Marine Studies University of Maryland University of Delaware College Park, Maryland 20742 Lewes, Delaware 19958 Cameron Ray Hackney Department of Food Science and Technology Virginia Polytechnic Institute and Technology and State University Blacksburg, Virginia 24601 Vll Introduction to the Special Symposium on Molluscan Introductions and Transfers: Risk Considerations and Implications ]ames T. Carlton and Aaron Rosenfield The collection of papers that appears within these proceedings of a great deal of attention. This attention is particularly strong is the outcome of a Symposium entitled ''Introductions and Trans­ among individuals and groups associated with intentional move­ fers of Mollusks: Risk Considerations and Implications". The ments of molluscan species, not only for aquaculture purposes but Symposium was held as part of the 82nd Annual Meeting of the also for scientific study, aquarium use, new product development National Shellfisheries Association in April 1990 in Williamsburg, and depuration. In addition others are interested in the unplanned, Virginia. One paper from this Symposium was publisherl earlier in accidental translocation of exotic mollusc species and transfers or this Journal (Mann et al. 1991). In addition to those papers that indigenous species, either of which when released into new envi­ appear here, six other papers were presented orally during the ronments may become nuisances themselves or act as carriers for Symposium. Unfortunately these latter papers were not completed other plants or animals that become pests, parasites, pathogens, or in time to be included in this issue of the Journal of Shellfish competitors with resident organisms. There are always risks asso­ Research. Although the editors would like to allow additional ciated with translocation of animals and plants resulting in impacts time, it was concluded that further delays would risk outdating the that could be either positive or negative from the viewpoints of papers submitted by the rest of the Symposium participants. environmental and resource sustainability. Careful consideration The Mollusca occur world wide in extraordinary diversity, must be given to the ecological, genetic, sociological, economic, abundance, and distribution both in aquatic and terrestrial habitats. aesthetic and political impacts that may result from undesirable They are readily available and harvestable; with common sense introductions regardless if they are deliberate or accidental. On the and a little knowledge and care they are among the easiest of the other hand, the use of mollusks for purposes of aquaculture, stock invertebrates to collect, manipulate, transport, and maintain for enhancement and improvement, sanitation, recreation, science and extended periods using relatively uncomplicated conditions and technology, education, and food production could bring enormous inexpensive holding facilities. It is no wonder their exploitation for benefits. However, such programs must be well thought out and food, ornamentation, dye materials, tools, construction material, carefully designed, and must be considerate of maintaining envi­ music, toys, utensils, money, and shell collections has been prac­ ronmental integrity and ecological balance. ticed for millennia. More recent imaginative and remarkable ad­ This Symposium thus considers some of these risks and ben­ vances have been made in the use of mollusks for aquaculture, efits involved with both known and anticipated introductions and genetic engineering (including the development of transgenics), transfers of mollusks, and discusses the potential implications, toxicology, and biomedicine. The use and application of mollusks past, present, and future, of these movements. in fields such as these necessarily involve the shipment and im­ We are most grateful to the National Marine Fisheries Service portation, that is, the translocation of mollusks from one location