Shellfish Aquaculture and the Environment E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 1125

Veröffentlichungsjahr: 2011

Beschreibung

Shellfish Aquaculture and the Environment focuses primarily on the issues surrounding environmental sustainability of shellfish aquaculture. The chapters in this book provide readers with the most current data available on topics such as resource enhancement and habitat restoration. Shellfish Aquaculture and the Environment is also an invaluable resource for those looking to develop and implement environmental best management practices. Edited one of the world's leading shellfish researchers and with contributions from around the world, Shellfish Aquaculture and the Environment is the definitive source of information for this increasingly important topic.

View the Executive Summary here:

http://seagrant.uconn.edu/publications/aquaculture/execsumm.pdf

Leseprobe

Table of Contents

Cover

Title page

Copyright page

Dedication

List of Contributors

Foreword

Preface

Chapter 1 The role of shellfish farms in provision of ecosystem goods and services

Introduction

Methods of study

Ecosystem goods: biomass production

Ecosystem services: environmental quality

Chapter 2 Shellfish aquaculture and the environment: an industry perspective

Introduction

Shellfish farmers and harvesters history of water quality protection and stewardship roles

BMPs, the shellfish industry, and the role of available research

Conclusion

Chapter 3 Molluscan shellfish aquaculture and best management practices

Introduction

Ecosystem change and shellfish aquaculture

Classification of impacts

BMPs

Assurance labeling

Pressures to participate in certification programs

Perspectives on ecolabeling

Aquaculture certification programs

Critique of bivalve shellfish ecolabeling efforts in the United States

Criticisms of certification programs

Towards more meaningful labeling

Concluding remarks

Chapter 4 Bivalve filter feeding: variability and limits of the aquaculture biofilter

Introduction

Constraints on maximum feeding activity

Shellfish feeding in nature

Emerging knowledge on ecosystem interactions with the bivalve biofilter

Conclusions

Chapter 5 Trophic interactions between phytoplankton and bivalve aquaculture

The interdependence of bivalves and phytoplankton

Bivalve population density: farmed bivalves are naturally gregarious

Bivalves as consumers and cultivators of phytoplankton

Summary and prospects

Acknowledgments

Chapter 6 The application of dynamic modeling to prediction of production carrying capacity in shellfish farming

Physical oceanographic models

Filtration and seston depletion

Single-box models

Higher-order models

Fully spatial models

Population-based models

Local models

Optimization

Application to management

Modeling environmental impact

Sustainability and ecosystem-based management

Chapter 7 Bivalve shellfish aquaculture and eutrophication

Summary

Introduction

Most commonly reported: localized changes associated with shellfish aquaculture

Interpretations from an ecosystem approach

Modeling efforts to assess relationships between bivalve aquaculture and eutrophication

Eutrophication of coastal waters from land-based nutrients

Ecological and economic benefit of bivalve aquaculture in combating eutrophication

Conclusions

Chapter 8 Mussel farming as a tool for re-eutrophication of coastal waters: experiences from Sweden

Introduction

Mussel farming: open landscape feeding in the sea

Estimating the environmental value of mussel farming

Trading nutrient discharges

Agricultural environmental aid program and mussel farming

Added ecosystem services through mussel farming

The city of lysekil, the first buyer of a nutrient emission quota

Swedish mussel farming and its markets

Mussel meal instead of fish meal in organic feeds

Mussel meal in feeds for organic poultry

The use of the mussel remainder as fertilizer and biogas production

Risk assessment of mussels for seafood, feed, and fertilizer

Conclusions of the Swedish experience

Chapter 9 Expanding shellfish aquaculture: a review of the ecological services provided by and impacts of native and cultured bivalves in shellfish-dominated ecosystems

Introduction

Aquaculture-based systems

Remaining questions

Chapter 10 Bivalves as bioturbators and bioirrigators

Bivalves are key species in soft-sediment habitats

What are bioturbation and bioirrigation?

How do healthy soft-sediment bivalve populations affect their surroundings?

Summary

Chapter 11 Environmental impacts related to mechanical harvest of cultured shellfish

Introduction

Literature review

Experimental design

Conclusions

Acknowledgments

Chapter 12 Genetics of shellfish on a human-dominated planet

Introduction

Domestication of shellfish

Conservation

Conclusions

Chapter 13 Shellfish diseases and health management

Shellfish health management and infectious disease prevention

Interactions of bivalve shellfish and parasites with the natural environment

Interactions of hosts and disease agents within the aquaculture environment

Solutions: 1. Shellfish aquaculture development and health management

Solutions: 2. Implementing health management for shellfish aquaculture

Summary

Chapter 14 Marine invaders and bivalve aquaculture: sources, impacts, and consequences

Introduction

Introduced shellfish from aquaculture

Species moved with aquaculture

Introduced species that impact aquaculture

Recommendations for minimizing spread and impacts of introductions

Future needs

Acknowledgments

Chapter 15 Balancing economic development and conservation of living marine resources and habitats: the role of resource managers

Introduction

Regulatory framework for shellfish aquaculture in the United States

Environmental best management practices (BMPs)

Environmental marketing and other incentive programs

Conclusions

Chapter 16 Education

Skills

Aquaculture-related disciplines

K-12 education

Undergraduate degree programs

Graduate degree programs

4-H and youth programs

Extension programs

Technology transfer

Conclusion

Chapter 17 The implications of global climate change for molluscan aquaculture

Introduction

Climate change in the oceans and coastal zones

The effects of climate change on shellfish aquaculture systems

Adapting shellfish farming to climate change impacts

Shellfish aquaculture and climate change mitigation

Conclusion

Acknowledgments

Index

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Library of Congress Cataloging-in-Publication Data

Shellfish aquaculture and the environment / edited by Sandra Shumway.

p. cm.

 Includes bibliographical references and index.

 ISBN 978-0-8138-1413-1 (hardcover : alk. paper) 1. Shellfish culture—Environmental aspects. I. Shumway, Sandra.

 SH370.S54 2011

 639'.4—dc22

2011011547

A catalogue record for this book is available from the British Library.

This book is published in the following electronic formats: ePDF 9780470960936; Wiley Online Library 9780470960967; ePub 9780470960943; Mobi 9780470960950

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The publisher and the author make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation warranties of fitness for a particular purpose. No warranty may be created or extended by sales or promotional materials. The advice and strategies contained herein may not be suitable for every situation. This work is sold with the understanding that the publisher is not engaged in rendering legal, accounting, or other professional services. If professional assistance is required, the services of a competent professional person should be sought. Neither the publisher nor the author shall be liable for damages arising herefrom. The fact that an organization or Website is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers should be aware that Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read.

For my parents, who launched my career at The Hummocks with a clam rake, a skiff, a 9.8 Johnson, and all the freedom, support, encouragement, and common sense a kid could ever need.

List of Contributors

Edward H. Allison

The WorldFish Center

Penang, Malaysia

Marie-Caroline Badjeck

The WorldFish Center

Penang, Malaysia

Edward P. Baker

Graduate School of Oceanography

University of Rhode Island

Narragansett, RI

Suzanne B. Bricker

National Oceanic and Atmospheric Administration

National Ocean Service

Silver Springs, MD

JoAnn M. Burkholder

Center of Applied Aquatic Ecology

North Carolina State University

Raleigh, NC

Daniel C. Cheney

Pacific Shellfish Institute

Olympia, WA

Loren D. Coen

16007 Waterleaf Lane

Ft. Myers, FL

Peter J. Cranford

Fisheries and Oceans Canada

Bedford Institute of Oceanography

Dartmouth, NS

Canada

Jonathan P. Davis

Taylor Shellfish Farms

Shelton, WA

William Dewey

Taylor Shellfish Farms

Shelton, WA

Brett R. Dumbauld

United States Department of Agriculture–Agricultural Research Service

Hatfield Marine Science Center

Newport, OR

Ralph A. Elston

AquaTechnics, Inc.

Sequim, WA

João G. Ferreira

Institute of Marine Research

New University of Lisbon

Portugal

Ramón Filgueira

Department of Oceanography

Dalhousie University

Canada

Susan E. Ford

Haskin Shellfish Research Laboratory

Rutgers University

Port Norris, NJ

Jon Grant

Department of Oceanography

Dalhousie University

Canada

Tessa L. Getchis

Connecticut Sea Grant

University of Connecticut

Groton, CT

John Hargreaves

Aquaculture Assessments LLC

Baton Rouge, LA

Bradley P. Harris

Department of Fisheries Oceanography

School for Marine Science and Technology

University of Massachusetts–Dartmouth

Fairhaven, MA

Anthony J.S. Hawkins

Plymouth Marine Laboratory

Plymouth, United Kingdom

Dennis Hedgecock

Department of Biology

University of Southern California

Los Angeles, CA

Michael L. Judge

Department of Biology

Manhattan College

Riverdale, NY

Odd Lindahl

The Royal Swedish Academy of Sciences

Stockholm, Sweden

Michael J. McCann

Department of Ecology and Evolution

Stony Brook University

Stony Brook, NY

Kathrin Meinhold

The WorldFish Center

Penang, Malaysia

Joanna Norkko

Tvärminne Zoological Station

University of Helsinki

Finland

Dianna K. Padilla

Department of Ecology and Evolution

Stony Brook University

Stony Brook, NY

Robert B. Rheault

East Coast Shellfish Growers Association

Wakefield, RI

Cori M. Rose

New England Division

U.S. Army Corps of Engineers

Concord, MA

Sandra E. Shumway

Department of Marine Sciences

University of Connecticut

Groton, CT

Kevin D.E. Stokesbury

Department of Fisheries Oceanography

School for Marine Science and Technology

University of Massachusetts–Dartmouth

Fairhaven, MA

J. Evan Ward

Department of Marine Sciences

University of Connecticut

Groton, CT

Donald Webster

Wye Research and Education Center

University of Maryland

Queenstown, MD

Gary H. Wikfors

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Northeast Fisheries Science Center

Milford, CT

Foreword

The publication of Shellfish Aquaculture and the Environment could not be more timely. At present, myriad local, state, federal, and private partners are working in the Gulf of Mexico to respond to the largest oil spill in our nation’s history. While the aftereffects of this disaster are not yet fully known, we do know that the environmental and economic ramifications will have significant long-term implications. This event, however, has made Americans nationwide deeply aware of the importance of healthy ecosystems, safe and sustainable fisheries, and the degree to which our economy—and in places like Louisiana and Mississippi, our national culture—depends on our relationship with and management of natural resources. No more so than now is our country aware of the importance of the complex fabric that interweaves our oceans and their ecosystems with the economies in coastal communities and beyond.

Shellfish play a central role in our marine ecosystems and coastal communities. Shellfish generate ecosystem benefits including water quality improvements and habitat and species restoration, while shellfish restoration and commercial shellfish aquaculture provide a local food supply and jobs that help to maintain working waterfronts. Conversely, shellfish farming and restoration can have negative environmental impacts, especially if best management practices are not followed.

Shellfish Aquaculture and the Environment addresses the environmental implications of shellfish aquaculture. This work began with the 2008 “Symposium on Shellfish and the Environment” in Warwick, Rhode Island, which brought together some of the finest researchers and policymakers from around the country to address the environmental benefits and challenges associated with shellfish aquaculture. Dr. Sandy Shumway worked with the National Oceanic and Atmospheric Administration’s (NOAA) Aquaculture and Habitat Programs to convene the symposium and invite the speakers. Many of those presentations were precursors to the chapters presented here.

As the Editor of the Journal of Shellfish Research for 25 years, research professor of marine sciences at the University of Connec­ticut, and a past president of the National Shellfisheries Association, Dr. Shumway is uniquely poised to communicate the profound role that shellfish aquaculture can play in supplying a source of safe, healthy, domestically sourced seafood as well as the critical ecological functions that shellfish serve. Dr. Shumway has focused her own research efforts on commercially important shellfish and has collaborated with scientists, communities, nongovernmental organizations, natural resource managers, government officials, and the shellfish aquaculture industry to facilitate public policy and resource management decisions for shellfish culture in the United States. Her commitment stems from her decades-long dedication to examining the interactions between shellfish and the environment. She recognizes that shellfish aquaculture is poised to make a significant contribution to the 37 million tons of seafood needed by 2030 to feed the world’s population—and do so in an ecologically sustainable manner.

Shellfish Aquaculture and the Environment is important on many practicable levels. It serves to inform resource managers and policymakers regarding the best available science on the environmental effects of shellfish aquaculture. It provides insights for managers and policymakers to communicate to scientists the information needed to foster informed decision making. It fosters infor­mation exchange that allows scientists to tailor research to answer specific questions to address potential limitations in shellfish aquaculture.

The NOAA Aquaculture Program has sought to advance the science of shellfish restoration and commercially viable, environmentally sustainable aquaculture. A robust domestic aquaculture industry promises to make a significant contribution to a safe, local, and healthy seafood supply. In a world in which the United States imports approximately 84% of its seafood—half of which comes from aquaculture—it is incumbent on us as consumers and stewards of the environment to take responsibility for our consumption decisions. Critical at this time especially, shellfish aquaculture serves as an economic engine, securing jobs in coastal communities, maintaining the spirit and energy of our working waterfronts, and supporting an array of secondary industries.

I would like to thank Dr. Shumway for being a visionary and conceiving of this book as well as doing the hard work of organizing, editing, and cajoling to bring it all to fruition. Sandy’s dedication to expanding scientific knowledge has strengthened our basis for making resource management decisions based on sound science. With Sandy’s help and that of so many others with a passion for ocean stewardship and sustainable fisheries, we continue to shine the national spotlight on the role that shellfish aquaculture can and should play in our nation’s seafood supply. Now comes the hard part of translating attention into action through commercial production, habitat restoration, focused research, economic incentives, and planning at the local, state, and federal levels. Shellfish Aquaculture and the Environment will be another valuable tool as for advancing the state and science of shellfish aquaculture.

Michael Rubino

Manager

NOAA Aquaculture Program

Preface

Aquaculture is the fastest growing sector of food production globally and has grown almost 10% annually for the past 50+ years. Aquaculture now provides half of the fisheries products consumed globally; 80% of the shellfish are cultured. It has been estimated that by 2050 food production will have to increase by 70% and there is little question that aquaculture—fish and shellfish and algae—will play a major role in that expansion. Only the rate, geographic distribution, and quality remain to be determined.

Shellfish aquaculture is poised to contribute substantially to this global need for food production; however, the political and scientific scrutiny is unprecedented. While the bulk of this scrutiny is focused on fish and shrimp culture, all aquaculture, including shellfish, is being watched very carefully. Just a decade ago, words such as “sustainable” and “ecosystem services” were foreign. Today, the seafood industry has “gone green” and having a “sustainably certified” label is an indispensable marketing tool.

Shellfish culture has, for many years, been unjustifiably grouped by the popular media with fish and other forms of aquaculture. Not only do the techniques differ extensively, but shellfish are primary consumers and thus no feed is used in the process. Shellfish culture, touted as the “green” culture, may have limited negative impacts in isolated and localized situations (usually associated with overstocking in suspended culture), but the bulk of available data demonstrate that, overall, the environmental impacts of shellfish aquaculture are minimal and most often beneficial. Shellfish aquaculture maintains working waterfronts, creates jobs, provides habitat for other organisms, removes excess nutrients from the water, and provides a multitude of other environmental services.

The task remains to change the perception of aquaculture among all stakeholders: researchers, managers, consumers, environmentalists, and policymakers. Sociopolitical issues such as multiuser conflicts, aesthetics, and recreational uses still prevail in many areas.

Clearly, introducing large densities of filter-feeding bivalve molluscs to a habitat, be it in suspended or bottom culture, may result in changes in the ecosystem. Changes can include depletion of phytoplankton, zooplankton, and seston, and localized increase in sedimentation rates via biodeposition, which in turn may induce organic enrichment and change sediment geochemistry and benthic community characteristics. The majority of impacts are site- and species-specific, and the detection and assessment of the influence of bivalve farming on the surrounding environs is a complex process.

Sustainable aquaculture provides a healthy source of protein, and is good for the environment and the economy; however, sustainability means different things to different groups and individuals. All farming and culture activities have environmental and social impacts. It is a complex array of interactions, and while ecosystem management approaches are key to addressing and solving the environmental issues, the socioeconomic issues associated with advancing sustainable shellfish aquaculture and embracing it as an environmentally and economically sound form of food production for future generations need and deserve a greater focus and presence.

The book consists of 17 chapters covering all aspects of shellfish aquaculture, and there was a concerted effort to engage scientists from other venues as well as those with a background in shellfish biology. All of the authors are experts in their respective fields; many are new to the shellfish arena and their willingness to participate in this project is deeply appreciated. Their participation has added appreciably to the overall substance of the book. Topics covered include the role of shellfish farms in provision of ecosystem goods and services; best management practices; filter feeding; trophic interactions between phytoplankton and bivalve aquaculture; the application of dynamic modeling to prediction of production carrying capacity in shellfish farming; eutrophication; mussel farming as a tool for re-eutrophication of coastal waters; bivalves as bioturbators and bioirrigators; environmental impacts of mechanical harvest of cultured shellfish; genetics; shellfish diseases and health management; marine invaders; economic development and conservation of living marine resources and habitats and the role of resource managers; education; implications of global climate change for molluscan aquaculture; and an industry perspective of future development of shellfish aquaculture.

The chapters in this book are not intended to be all-inclusive review papers. They are meant to provide readable and understandable background information on key issues associated with shellfish aquaculture to resource managers and policymakers, to help translate the results of scientific research into sound policy, and ensure the continued growth of sustainable molluscan aquaculture.

It is hoped that this book will provide background information necessary on key parameters to assist in new sitings and expansion of existing aquaculture operations, habitat management, and potential restoration or enhancement efforts. It will also provide baseline information to aid in the development and evaluation of best management practices critical to responsible environmental stewardship. It will allow policymakers and managers to reach informed and reasonable decisions in a timely fashion as sustainable molluscan aquaculture continues to expand and take its place in the global arena as the need for increased seafood production continues to grow.

Shellfish aquaculture provides ecosystem services and a healthy source of protein. There are challenges ahead that require all stakeholders—scientists, managers, policymakers, citizens, and aquaculturists alike—to adopt a holistic, realistic, and integrated view toward assessing and weighing the impacts and benefits associated with shellfish aquaculture, and to make informed decisions regarding acceptable impacts. It is time to take the “big picture” approach. Policymakers and managers need to be acutely aware of the big picture to make informed decisions. The future of aquaculture relies on a balance between research and common sense. Overregulation and unrealistic or unnecessary restraints in the name of caution—often a synonym for “afraid to take a stand”—will only slow a necessary and sustainable process. If shellfish aquaculture is to flourish, all constituents need to work together—the future of molluscan shellfish aquaculture and increased food production depends on it.

This book would not have been possible without the financial and intellectual support of many people and agencies. First and foremost, thank you to the National Oceanic and Atmospheric Administration (NOAA) Aquaculture Program, especially Michael Rubino, Kate Naughten, and Brian Fredieu for their unflagging support and guidance in moving shellfish aquaculture to the forefront of recognition and acceptance. Justin Jeffryes of Wiley-Blackwell has provided continued support and great patience. Kari Heinonen was an invaluable source of technical expertise and performed endless thankless tasks and the book would not have materialized with­out her.

The book is representative of a group effort and I extend my heartfelt thanks to all the authors for sharing their time and expertise, to the reviewers for their timely input, and to the industry members who have regularly tried to keep me grounded, especially Leroy Creswell, Chris Davis, Joth Davis, Bill Dewey, Robin Downey, Rick Karney, Carter Newell, and Bob Rheault. I hope the final product has done justice to their collective efforts.

And finally, a special thanks to my furry associates, Gus and Zeus, who made all those long evenings of editing and proofreading a little easier to endure.

Sandra E. Shumway

Groton, CT

This book was prepared by Sandra Shumway under award number NA08OAR4170834 from the National Oceanographic and Atmospheric Administration (NOAA) Marine Aquaculture Program, U.S. Department of Commerce.

Chapter 1

The role of shellfish farms in provision of ecosystem goods and services

João G. Ferreira, Anthony J.S. Hawkins, and Suzanne B. Bricker

Introduction

What Is a Farm?

Shellfish farms vary widely in type, situation, and size. The type of culture can vary according to species, and even within the same species various approaches may be used, depending on factors such as tradition, environmental conditions, and social acceptance. For instance, mussels are cultivated on rafts in Galicia (Spain), and on longlines in the Adriatic Sea (Fabi et al. 2009). But they are also grown on poles in the intertidal area in both France (bouchot) and China (muli zhuang), or dredged from the bottom in Carlingford Lough (Ireland) and in the Eastern Scheldt (the Netherlands).

It is not unusual to use different culture techniques for the same species at different stages of the growth cycle, or to rear benthic organisms off-bottom, taking advantage of a greater exposure to pelagic primary production, better oxygenation, and predator exclusion.

In a similar way, shellfish can be grown in intertidal areas, competing for space with other uses (e.g., geoduck grown in PVC tubes in Puget Sound, USA; oysters on trestles in Dungarvan Harbour, Ireland), or subtidally (e.g., scallop off Zhangzidao Island, northeast China). Cultivation takes place within estuaries, coastal lagoons, and bays (e.g., Figure 1.1), and increasingly in offshore locations, where there are less conflicts with other stakeholders in the coastal zone. In many parts of the world, onshore cultivation is also a reality, as occurs in Guangdong province (China) and elsewhere for razor clams and oysters, frequently in multispecies combinations (e.g., Ferreira et al. 2008a; Zhang et al. 2009; Nobre et al. 2010).

Figure 1.1 Aquaculture in Sanggou Bay, northeast China. Longlines used for shellfish culture are clearly visible in satellite images.

The size of farms may vary widely, given various constraints imposed by physical space, environmental conditions (which directly influence production), ecological effects, and social acceptability. An obvious constraint on the viability of a shellfish farm is the natural food supply, which in some areas of the world has a direct relationship to the lease units. For instance, in China, the aquaculture cultivation unit is the Culture Mu (Nunes et al. 2003); in a similar way to the medieval bushel, the actual area of this unit varies among different bays, depending on the typical carrying capacity per unit area of each bay, as exemplified in Table 1.1 for Shandong province.

Table 1.1 Dependency of Chinese lease units on carrying capacity.

Bay or systemUnit nameArea (m2)All land-based agricultureMu666.66 (1/15 ha)Sanggou BayCulture Mu1600–1800Jiaozhou BayCulture Mu3000–5000Laizhou BayCulture Mu5000–8000

For the purposes of this text, a farm is therefore defined as an integrated production unit, typically allocated as a lease, subject to specific pressures with associated impacts (Fig. 1.2). This can be an area of sea bottom where molluscs are grown (e.g., mussel/oyster culture, abalone in pens), off-bottom (but overlying bottom space) such as oyster trestles, or an area of water where rafts or lines are placed (droppers off longlines, Chinese lanterns), or ponds fringing coastal areas (razor clams). Whether farms are located on the bottom, off-bottom, or as suspended structures, they generally preclude the use of the sea bottom for other human activities, such as fishing or recreation, and raise controversial issues related to multiuser interactions, as discussed in Chapter 9 (in this book).

Figure 1.2 Aquaculture farms: illustration of pressures, activities, and impacts on the coastal fringe.

This chapter examines the role of the shellfish farm as a provider of ecosystem goods and services. The focus is on farms located in open estuarine and marine waters, from the intertidal zone to offshore locations. Although this book is aimed at shellfish ( bivalve mollusc) aquaculture, it is impossible to address the current state of the art of shellfish farming without the inclusion of integrated multitrophic aquaculture (IMTA), an approach that has been practiced in Southeast Asia for thousands of years, both in ponds and in open systems (Ferreira et al. 2008a), and is currently attracting considerable interest (Neori et al. 2004; Ridler et al. 2007; Paltzata et al. 2008).