A Simple Method for Estimating MSY from Catch and Resilience
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Three Simple Rules for High Catches, High Profits and Healthy Ecosystems
Three simple rules for high catches, high profits and healthy ecosystems Position paper for the round-table discussion Towards a Sustainable Fishery Sector Block 2, Interactions between Fisheries and Nature, Wednesday 23 June 2021 by Rainer Froese, GEOMAR, Kiel, Germany, [email protected] Rule 1: Do not take out more than is regrown Taking out more than is regrown is called overfishing and will shrink the fished stock below levels that can produce the maximum longterm catch (MSY). Despite the legal obligation to end overfishing in 2020, the total allowed catches (TACs) for about 40% of the stocks with suitable data in the North Sea and adjacent waters constituted overfishing (1). Overfishing is stupid: with overfishing, more effort = money is spent to get lower catches than possible at lower value and with unnecessarily high impacts on the ecosystem. The lower value is caused by overfishing shrinking the mean size of the fish and smaller fish bring lower price per kg. Impact is unnecessary high because better catches can be obtained from non- overfished stocks with less gear deployment, therefore less by-catch and less physical impact. To end overfishing, catches have to be reduced for 1-4 years, depending on current stock size. The loss caused by such reduced catches is easily regained within a few years after rebuilt stock size allows for permanent high catches at e.g. 90% of the MSY level. The 90% MSY is needed for stability; with fishing at MSY, there is a 50% chance of shrinking the stock below the MSY level and thus reducing future catches. -
Structure and Dynamics of Demersal Assemblages on the Continental Shelf and Upper Slope Off Ghana, West Africa
MARINE ECOLOGY PROGRESS SERIES Vol. 220: 1–12, 2001 Published September 27 Mar Ecol Prog Ser Structure and dynamics of demersal assemblages on the continental shelf and upper slope off Ghana, West Africa Kwame A. Koranteng* Marine Fisheries Research Division, PO Box BT-62, Tema, Ghana ABSTRACT: Using two-way indicator species analysis and detrended correspondence analysis, species on the continental shelf and upper slope of Ghana were classified into 6 assemblages. The structure of the assemblages is determined primarily by depth and type of sediment on the seabed. There are clear faunal discontinuities around 30–40, 100 and 200 m depth. The dynamics of the assemblages are influenced by physico-chemical parameters of the water masses, mainly tempera- ture, salinity and dissolved oxygen, which are periodically modified by the seasonal coastal upwelling that occurs in the area. The observed changes in the composition and relative importance of species in the assemblages can be related to increased fishing activity and environmental forcing. KEY WORDS: Species assemblages · Structure and dynamics · Continental shelf and slope · Ghana Resale or republication not permitted without written consent of the publisher INTRODUCTION nental shelf using data from the Guinean Trawling Survey (Williams 1968). In fisheries, defining the aggregation of species in In the last 3 decades, significant changes have the ecosystem is the basis for managing species by the occurred in the biological and physical components of management unit approach (Tyler et al. 1982). Caddy the Gulf of Guinea marine ecosystem and in nearshore & Sharp (1986) also pointed out that such studies are forcing factors that could have an effect on species necessary to gain a better understanding of multi- aggregations in the sub-region (Koranteng 1998). -
Production and Maximum Sustainable Yield of Fisheries Activity in Hulu Sungai Utara Regency
E3S Web of Conferences 147, 02008 (2020) https://doi.org/10.1051/e3sconf/202014702008 3rd ISMFR Production and Maximum Sustainable Yield of fisheries activity in Hulu Sungai Utara Regency Aroef Hukmanan Rais* and Tuah Nanda Merlia Wulandari Balai Riset Perikanan Perairan Umum dan Penyuluhan Perikanan, Jln. Gub. HA Bastari, No.08 Jakabaring, Palembang, Indonesia Abstract. Production and fishing activities of inland waters in the Hulu Sungai Utara Regency (HSU) have a large contribution to fulfill the food needs for the local people in South Borneo. A total of 65% of the inland waters in the HSU Regency are floodplains. This research aimed to describe the production of capture fisheries products from 2010 to 2016, the catch per unit of effort (CPUE), the estimation of maximum sustainable (MSY), the biodiversity of fish species in the flood plain waters of Hulu Sungai Utara Regency (HSU). Research and field data collection was carried out throughout 2016, by collecting fishing gears and catch data from fishermen at Tampakang Village and Palbatu Village. The highest fish production was found in 2014, which reached a value of 2053 tons/year, and tended to decline in the following year. The highest catch per unit of effort per year was found to be in 2014 (151.65 tons/effort), and significantly dropped in 2016 (36.05 tons/effort). The Maximum Sustainable Yield (MSY) analysis obtained a value of 2103.13 tons/year with an effort value of 16.57 for standard fishing gear. The research identified 31 species of fish and the largest composition was baung (Mystusnemurus) and Nila (Tilapia nilotica). -
Stock Assessment of Sardine (Sardina Pilchardus, Walb.) in the Adriatic Sea, with an Estimate of Discards*
sm69n4603-1977 21/11/05 16:28 Página 603 SCI. MAR., 69 (4): 603-617 SCIENTIA MARINA 2005 Stock assessment of sardine (Sardina pilchardus, Walb.) in the Adriatic Sea, with an estimate of discards* ALBERTO SANTOJANNI 1, NANDO CINGOLANI 1, ENRICO ARNERI 1, GEOFF KIRKWOOD 2, ANDREA BELARDINELLI 1, GIANFRANCO GIANNETTI 1, SABRINA COLELLA 1, FORTUNATA DONATO 1 and CATHERINE BARRY 3 1 ISMAR - CNR, Sezione Pesca Marittima, Largo Fiera della Pesca, 60125 Ancona, Italy. E-mail: [email protected] 2 Renewable Resources Assessment Group (RRAG), Department of Environmental Science and Technology, Imperial College, Prince Consort Road, London, UK. 3 Marine Resources Assessment Group (MRAG), 27 Campden Street, London, UK. SUMMARY:Analytical stock assessment of sardine (Sardina pilchardus, Walb.) in the Adriatic Sea from 1975 to 1999 was performed taking into account the occurrence of discarding at sea of sardine caught by the Italian fleet. We have attempted to model the fishermen’s behaviour using data collected by an observer on board fishing vessels. This enabled us to estimate the amounts of discards, which were added to the catches landed, collected by ISMAR-CNR Ancona. Discards were calculated for the period 1987-1999, as their values were negligible before 1987. Stock assessment on the entire data series from 1975-1999 was carried out by means of Virtual Population Analysis (VPA). Discarding behaviour differs among ports due to different local customs and market conditions. The quantity added to the annual total catch ranged from 900 tonnes to 4000 tonnes, corre- sponding to between 2% and 15% of the total corrected catch. -
Welcome to Fishbase
Welcome to FishBase FishBase contains different things for different people FishBase is an information system with key data on the biology of all fishes. Similar to an encyclopedia, FishBase contains different things for different people. For example, fisheries managers will dive into the largest existing compilation of population dynamics data; teachers and students will find numerous graphs illustrating basic concepts of fish biology; conservationists will use the lists of threatened fishes for any given country; policymakers may be interested in a chronological, annotated list of introductions to their country; research scientists, as well as funding agencies, will find it useful to gain a quick overview of what is known about a certain species; zoologists and physiologists will have the largest existing compilations of fish morphology, metabolism, gill area, brain size, eye pigment, or swimming speed at their fingertips; ecologists will likewise use data on diet composition, trophic levels, food consumption and predators as inputs for their models; the fishing industry will find proximate analyses, as well as processing recommendations for many marine species; anglers will enjoy a listing of all game fishes occurring in a particular country; and scholars interested in local knowledge will find more than 300,000 common names of fishes together with the language/culture in which they are used and comments on their etymology. Unexpected usage of FishBase The above text shows the usage of FishBase that we expected when we first published it on CD- ROM and later on the Internet, in the late 1990s. That assessment has been largely correct with regard to scientific use, which led to over 5000 citations of FishBase as counted by Google Scholar. -
Seafood Watch® Standard for Fisheries
1 Seafood Watch® Standard for Fisheries Table of Contents Table of Contents ............................................................................................................................... 1 Introduction ...................................................................................................................................... 2 Seafood Watch Guiding Principles ...................................................................................................... 3 Seafood Watch Criteria and Scoring Methodology for Fisheries ........................................................... 5 Criterion 1 – Impacts on the Species Under Assessment ...................................................................... 8 Factor 1.1 Abundance .................................................................................................................... 9 Factor 1.2 Fishing Mortality ......................................................................................................... 19 Criterion 2 – Impacts on Other Capture Species ................................................................................ 22 Factor 2.1 Abundance .................................................................................................................. 26 Factor 2.2 Fishing Mortality ......................................................................................................... 27 Factor 2.3 Modifying Factor: Discards and Bait Use .................................................................... 29 Criterion -
Potential Indicators and Reference Points for Good Environmental Status of Commercially Exploited Marine Fishes and Invertebrates in the German EEZ
Potential Indicators and Reference Points for Good Environmental Status of Commercially Exploited Marine Fishes and Invertebrates in the German EEZ Rainer Froese, Helmholtz Centre for Ocean Research GEOMAR, Düsternbrooker Weg 20, Germany, [email protected] Arlene Sampang, FishBase Information and Research Group FIN, Khush Hall, IRRI, Los Baños, Laguna, Philippines, [email protected] Cite as: Froese, R. and A. Sampang. 2013. Potential Indicators and Reference Points for Good Environmental Status of Commercially Exploited Marine Fishes and Invertebrates in the German EEZ. World Wide Web electronic publication, available from http://oceanrep.geomar.de/22079/ Note: This version of the text [MSFD_8.pdf] replaces an earlier version [MSFD_5.pdf] of September 2013. It fixes a misalignment of proxy recruits and spawners in the data-limited stocks and adds an indication of total biomass. It also adds an analysis of commercial catch data relative to stock abundance, to improve the estimation of mortality for the data-limited stocks. The concepts, overall results and conclusions are not affected by these changes. Abstract Indicators and reference points for assessing the good environmental status of commercially exploited marine fishes and invertebrates are presented, using 20 stocks from the German exclusive economic zone. New estimates of length-weight relationship, von Bertalanffy growth, length at 50% and 90% maturity, age at 50% maturity, and length and age where cohort biomass is maximum are presented for each stock. Twice the stock size below which recruitment may become impaired (SSBpa) is proposed as a proxy for the biomass that can produce the maximum sustainable yield, which is the lower limit reference point for stock size. -
Estimating Discards Using Selectivity Data: the Effects of Mesh Size Changes in the Mixed Demersal Fisheries in the Irish Sea
NOT TO BE CITED WITHOUT PRIOR REFERENCE TO THE AUTHOR(S) Northwest Atlantic Fisheries Organization Serial No. N2302 NAFO SCR Doc. 93/109 SCIENTIFIC COUNCIL MEETING - SEPTEMBER 1993 'Estimating Discards Using Selectivity Data: the Effects of Mesh Size Changes in the Mixed Demersal Fisheries in the Irish Sea. by J. Casey Ministry of Agriculture, Fisheries and Food Directorate of Fisheries Research Fisheries Laboratory Pakefield Road, Lowestoft, Suffolk NR33 OHT, U.K. Abstract A model is described to predict the numbers at age of fish discarded in fisheries for which only landings at age are known. The model assumes a knowledge of the E distributionoflengthwiftneachagegroupindiepoputhfion,andusesmeshselection 0 characteristics, and an inferred discarding practice, to derive the proportions of each 0 age group discarded and landed. Mesh selectivity and discarding practice, in terms of 0 proportions of the catch discarded and landed, are described using a logistic fit to the proportions of the population entering the net that are caught, discarded and landed. The application of the model is illustrated using data from the mixed demersal fisheries 11 .1 in the Irish Sea, and the effects of mesh size and effort changes on catch predictions are examined. 71-5 t9 Introduction Catches of finfish in the Irish Sea are dominated by four main species; the common sole (Solea solea (Linnaeus, 1758)), plaice (Pleuronectesplatessa Linnaeus, 1758), cod (Gadus morhua Linnaeus, 1758) and whiting (Merlangias merlangus (Linnaeus, 1758)). The demersal fishery for these species in the Irish Sea is prosecuted by 3 main fleets, each using a different gear type; beam trawlers, otter trawlers and Nephrops trawlers. -
A Guide to Fisheries Stock Assessment from Data to Recommendations
A Guide to Fisheries Stock Assessment From Data to Recommendations Andrew B. Cooper Department of Natural Resources University of New Hampshire Fish are born, they grow, they reproduce and they die – whether from natural causes or from fishing. That’s it. Modelers just use complicated (or not so complicated) math to iron out the details. A Guide to Fisheries Stock Assessment From Data to Recommendations Andrew B. Cooper Department of Natural Resources University of New Hampshire Edited and designed by Kirsten Weir This publication was supported by the National Sea Grant NH Sea Grant College Program College Program of the US Department of Commerce’s Kingman Farm, University of New Hampshire National Oceanic and Atmospheric Administration under Durham, NH 03824 NOAA grant #NA16RG1035. The views expressed herein do 603.749.1565 not necessarily reflect the views of any of those organizations. www.seagrant.unh.edu Acknowledgements Funding for this publication was provided by New Hampshire Sea Grant (NHSG) and the Northeast Consortium (NEC). Thanks go to Ann Bucklin, Brian Doyle and Jonathan Pennock of NHSG and to Troy Hartley of NEC for guidance, support and patience and to Kirsten Weir of NHSG for edit- ing, graphics and layout. Thanks for reviews, comments and suggestions go to Kenneth Beal, retired assistant director of state, federal & constituent programs, National Marine Fisheries Service; Steve Cadrin, director of the NOAA/UMass Cooperative Marine Education and Research Program; David Goethel, commercial fisherman, Hampton, NH; Vincenzo Russo, commercial fisherman, Gloucester, MA; Domenic Sanfilippo, commercial fisherman, Gloucester, MA; Andy Rosenberg, UNH professor of natural resources; Lorelei Stevens, associate editor of Commercial Fisheries News; and Steve Adams, Rollie Barnaby, Pingguo He, Ken LaValley and Mark Wiley, all of NHSG. -
Wasted Catch: Unsolved Problems in U.S. Fisheries
© Brian Skerry WASTED CATCH: UNSOLVED PROBLEMS IN U.S. FISHERIES Authors: Amanda Keledjian, Gib Brogan, Beth Lowell, Jon Warrenchuk, Ben Enticknap, Geoff Shester, Michael Hirshfield and Dominique Cano-Stocco CORRECTION: This report referenced a bycatch rate of 40% as determined by Davies et al. 2009, however that calculation used a broader definition of bycatch than is standard. According to bycatch as defined in this report and elsewhere, the most recent analyses show a rate of approximately 10% (Zeller et al. 2017; FAO 2018). © Brian Skerry ACCORDING TO SOME ESTIMATES, GLOBAL BYCATCH MAY AMOUNT TO 40 PERCENT OF THE WORLD’S CATCH, TOTALING 63 BILLION POUNDS PER YEAR CORRECTION: This report referenced a bycatch rate of 40% as determined by Davies et al. 2009, however that calculation used a broader definition of bycatch than is standard. According to bycatch as defined in this report and elsewhere, the most recent analyses show a rate of approximately 10% (Zeller et al. 2017; FAO 2018). CONTENTS 05 Executive Summary 06 Quick Facts 06 What Is Bycatch? 08 Bycatch Is An Undocumented Problem 10 Bycatch Occurs Every Day In The U.S. 15 Notable Progress, But No Solution 26 Nine Dirty Fisheries 37 National Policies To Minimize Bycatch 39 Recommendations 39 Conclusion 40 Oceana Reducing Bycatch: A Timeline 42 References ACKNOWLEDGEMENTS The authors would like to thank Jennifer Hueting and In-House Creative for graphic design and the following individuals for their contributions during the development and review of this report: Eric Bilsky, Dustin Cranor, Mike LeVine, Susan Murray, Jackie Savitz, Amelia Vorpahl, Sara Young and Beckie Zisser. -
Wasted Resources: Bycatch and Discards in U. S. Fisheries
Wasted Resources: Bycatch and discards in U. S. Fisheries by J. M. Harrington, MRAG Americas, Inc. R. A. Myers, Dalhousie University A. A. Rosenberg, University of New Hampshire Prepared by MRAG Americas, Inc. For Oceana July 2005 TABLE OF CONTENTS ACKNOWLEDGEMENTS 7 NATIONAL OVERVIEW 9 Introduction 9 Methodology 11 Discarded Bycatch Estimates for the 27 Major Fisheries in the U.S. 12 Recommendations 17 Definitions of Key Terms Used in the Report 19 Acronyms and Abbreviations Used in the Report 20 NORTHEAST 25 Northeast Groundfish Fishery 27 Target landings 28 Regulations 30 Discards 32 Squid, Mackerel and Butterfish Fishery 41 Target landings 42 Regulations 44 Discards 44 Monkfish Fishery 53 Target landings 53 Regulations 54 Discards 55 Summer Flounder, Scup, and Black Sea Bass Fishery 59 Target landings 59 Regulations 60 Discards 61 Spiny Dogfish Fishery 69 Target landings 69 Regulations 70 Discards 70 Atlantic Surf Clam and Ocean Quahog Fishery 75 Target landings 75 Regulations 76 Discards 76 Atlantic Sea Scallop Fishery 79 Target landings 79 Regulations 80 Discards 81 Atlantic Sea Herring Fishery 85 Target landings 85 Regulations 86 Discards 87 Northern Golden Tilefish Fishery 93 Target landings 93 Regulations 94 Discards 94 Atlantic Bluefish Fishery 97 Target landings 97 Regulations 98 Discards 98 Deep Sea Red Crab Fishery 101 Target landings 101 Regulations 101 Discards 102 SOUTHEAST 103 Shrimp Fishery of the South Atlantic 105 Target landings 105 Regulations 106 Discards 107 Snapper and Grouper of the South Atlantic 111 Target -
UNDER PRESSURE. the Need to Protect Whales and Dolphins In
UNDER PRESSURE The need to protect whales and dolphins in European waters The need to protect whales and dolphins in European waters April 2021 An OceanCare report. © OceanCare 2021 ISBN 978-3-033-08516-9 Editor: Laetitia Nunny, Wild Animal Welfare, La Garriga, Spain Cover image: © gettyimages Design: Roman Richter Suggested citation: OceanCare (2021) Under Pressure: The need to protect whales and dolphins in European waters. An OceanCare report. Copyright: The copyright of individual articles (including research articles, opinion pieces, conference proceedings, abstracts and images) remains the property of the authors. OceanCare Gerbestrasse 6 P.O.Box 372 CH-8820 Wädenswil Switzerland Tel: +41 (0) 44 780 66 88 https://www.oceancare.org OceanCare has been committed to marine wildlife protection since 1989. Through research and conservation projects, campaigns, environmental education, and involvement in a range of important international committees, OceanCare undertakes concrete steps to improve the situation for wildlife in the world’s oceans. OceanCare holds Special Consultative Status with the Economic and Social Council of the United Nations (ECOSOC) and is a partner of the General Fisheries Commission for the Mediterranean (GFCM), the Convention on Migratory Species (CMS), and the UNEP/CMS Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS), as well as UNEP/MAP. OceanCare is accredited observer at the Convention on Biological Diversity (CBD). OceanCare has also been accredited as a Major Group to the United Nations Environment Assembly (UNEA), which is the governing body of UNEP and is a part of the UNEP Global Partnership on Marine Litter.