23. Fish Stocks and Fish Landings
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Virtual Population Analysis
1 INTRODUCTION 1.1 OVERVIEW There are a variety of VPA-type methods, which form powerful tools for stock assessment. At first sight, the large number of methods and their arcane names can put off the newcomer. However, this complexity is based on simple common components. All these methods use age-structured data to assess the state of a stock. The stock assessment is based on a population dynamics model, which defines how the age-structure changes through time. This model is the simplest possible description of numbers of similar aged fish where we wish to account for decreases in stock size through fishing activities. The diversity of VPA methods comes from the way they use different types of data and the way they are fitted. This manual is structured to describe the different components that make up a VPA stock assessment model: Population Model (Analytical Model) The population model is the common element among all VPA methods. The model defines the number of fish in a cohort based on the fishing history and age of the fish. A cohort is a set of fish all having (approximately) the same age, which gain no new members after recruitment, but decline through mortality. The fisheries model attempts to measure the impact catches have on the population. The population model usually will encapsulate the time series aspects of change and should include any random effects on the population (process errors), if any. Link Model Only rarely can variables in which we are interested be observed directly. Usually data consists of observations on variables that are only indirectly linked to variables of interest in the population model. -
The State of Mediterranean and Black Sea Fisheries 2018
Food and Agriculture General Fisheries Commission for the Mediterranean Organization of the Commission générale des pêches United Nations pour la Méditerranée ISSN 2413-6905 THE STATE OF MEDITERRANEAN AND BLACK SEA FISHERIES 2018 Reference: FAO. 2018. The State of Mediterranean and Black Sea Fisheries General Fisheries Commission for the Mediterranean. Rome, Italy. pp. 164. THE STATE OF MEDITERRANEAN AND BLACK SEA FISHERIES 2018 FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Rome, 2018 Required citation: FAO. 2018. The State of Mediterranean and Black Sea Fisheries. General Fisheries Commission for the Mediterranean. Rome. 172 pp. The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specifc companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily refect the views or policies of FAO. ISBN 978-92-5-131152-3 © FAO, 2018 Some rights reserved. This work is made available under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 IGO licence (CC BY-NC-SA 3.0 IGO; https://creativecommons.org/licenses/by-nc-sa/3.0/igo/legalcode/legalcode). -
Updated Checklist of Marine Fishes (Chordata: Craniata) from Portugal and the Proposed Extension of the Portuguese Continental Shelf
European Journal of Taxonomy 73: 1-73 ISSN 2118-9773 http://dx.doi.org/10.5852/ejt.2014.73 www.europeanjournaloftaxonomy.eu 2014 · Carneiro M. et al. This work is licensed under a Creative Commons Attribution 3.0 License. Monograph urn:lsid:zoobank.org:pub:9A5F217D-8E7B-448A-9CAB-2CCC9CC6F857 Updated checklist of marine fishes (Chordata: Craniata) from Portugal and the proposed extension of the Portuguese continental shelf Miguel CARNEIRO1,5, Rogélia MARTINS2,6, Monica LANDI*,3,7 & Filipe O. COSTA4,8 1,2 DIV-RP (Modelling and Management Fishery Resources Division), Instituto Português do Mar e da Atmosfera, Av. Brasilia 1449-006 Lisboa, Portugal. E-mail: [email protected], [email protected] 3,4 CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. E-mail: [email protected], [email protected] * corresponding author: [email protected] 5 urn:lsid:zoobank.org:author:90A98A50-327E-4648-9DCE-75709C7A2472 6 urn:lsid:zoobank.org:author:1EB6DE00-9E91-407C-B7C4-34F31F29FD88 7 urn:lsid:zoobank.org:author:6D3AC760-77F2-4CFA-B5C7-665CB07F4CEB 8 urn:lsid:zoobank.org:author:48E53CF3-71C8-403C-BECD-10B20B3C15B4 Abstract. The study of the Portuguese marine ichthyofauna has a long historical tradition, rooted back in the 18th Century. Here we present an annotated checklist of the marine fishes from Portuguese waters, including the area encompassed by the proposed extension of the Portuguese continental shelf and the Economic Exclusive Zone (EEZ). The list is based on historical literature records and taxon occurrence data obtained from natural history collections, together with new revisions and occurrences. -
Sardina Pilchardus Walbaum, 1792) and European Anchovy (Engraulis Encrasicolus Linnaeus, 1758) in the Izmir Bay (Aegean Sea, Turkey) Purse Seine Fishery
Mar. Sci. Tech. Bull. (2020) 9(1): 32–37 dergipark.org.tr/en/pub/masteb e–ISSN: 2147–9666 www.masteb.com [email protected] DOI: 10.33714/masteb.673318 RESEARCH ARTICLE Length-weight relationship of the most landed pelagic fish species European pilchard (Sardina pilchardus Walbaum, 1792) and European anchovy (Engraulis encrasicolus Linnaeus, 1758) in the Izmir Bay (Aegean Sea, Turkey) purse seine fishery Ahmet Mert Şenbahar1* • Özlem Güleç2 • Zafer Tosunoğlu2 • Okan Özaydın1 1 Ege University, Faculty of Fisheries, Department of Marine-Inland Waters Sciences and Technology, 35100, Bornova, Izmir, Turkey 2 Ege University, Faculty of Fisheries, Department of Fishing and Processing Technology, 35100, Bornova, Izmir, Turkey ARTICLE INFO ABSTRACT Article History: Length-weight relationships (LWR) of the most landed pelagic fish species Sardina pilchardus Walbaum, 1792 and Engraulis encrasicolus Linnaeus, 1758 in the Izmir Bay Received: 10.01.2020 purse seine fishery were determined to reveal latest situation. Purse seine is a non-selective Received in revised form: 04.02.2020 fishing gear compare to the other fishing gear such as gillnet or trammel net. For this Accepted: 04.02.2020 reason, sampling all size individuals is very important to calculate mean length and other Available online: 05.02.2020 LWR parameters. In this study, seasonal LWR coefficient and minimum-maximum lengths Keywords: were established as monthly basis. LWR of S. pilchardus and E. encrasicolus were W = Sardine pilchardus 0.0059L2.7930 (r² = 0.94) and W = 0.0019L3.4207, (r² = 0.87), respectively. Growth type of the Engraulis encrasicolus S. pilchardus was found negative allometric whereas E. -
A Fish in Water: Sustainable Canadian Atlantic Fisheries Management and International Law
COMMENT A FISH IN WATER: SUSTAINABLE CANADIAN ATLANTIC FISHERIES MANAGEMENT AND INTERNATIONAL LAW ANDREW FAGENHOLZ* 1. INTRODUCTION The health and viability of the world's fisheries have declined dramatically over the past twenty years, and today most fisheries are too close to collapse.' Overexploitation of world fisheries has resulted from traditional international law that treated the oceans as a commons, or mare liberum,2 and their fish as susceptible to * J.D. Candidate, University of Pennsylvania Law School, 2004; B.A., Williams College, 1998. The author wishes to thank Professor Jason Johnston for teaching the course that inspired this paper, Professor Harry N. Scheiber for assistance, the members of this Journal, and R. Andrew Price. 1 See The State of the World Fisheries and Aquaculture: Part I - World Review of Fisheries and Aquaculture, U.N. Food and Agriculture Organization ("FAO") (2002) (designating global fisheries in 2002 as forty-seven percent fully exploited, eight- een percent overexploited, twenty-five percent moderately exploited or underex- ploited, ten percent depleted or recovering), available at http://www. fao.org/docrep/ 005/y7300e/y7300e04.htm (last visited Mar. 26, 2004). The U.N. Food and Agriculture Organization has been called the "most authoritative statis- tical source on the subject" of global fisheries populations. Christopher J. Carr & Harry N. Scheiber, Dealing with a Resource Crisis: Regulatory Regimes for Managing the World's Marine Fisheries, 21 STAN. ENVTL. L.J. 45, 46 (2002). 2 HUGO GROTIUS, MARE LIBERUM (THE FREEDOM OF THE SEAS) 28 (James B. Scott ed., Ralph Van Deman Magoffin trans., 1916) (1633). In the seventeenth century it was generally thought that global fish resources were incapable of exhaustion by humankind. -
Other Processes Regulating Ecosystem Productivity and Fish Production in the Western Indian Ocean Andrew Bakun, Claude Ray, and Salvador Lluch-Cota
CoaStalUpwellinO' and Other Processes Regulating Ecosystem Productivity and Fish Production in the Western Indian Ocean Andrew Bakun, Claude Ray, and Salvador Lluch-Cota Abstract /1 Theseasonal intensity of wind-induced coastal upwelling in the western Indian Ocean is investigated. The upwelling off Northeast Somalia stands out as the dominant upwelling feature in the region, producing by far the strongest seasonal upwelling pulse that exists as a; regular feature in any ocean on our planet. It is surmised that the productive pelagic fish habitat off Southwest India may owe its particularly favorable attributes to coastal trapped wave propagation originating in a region of very strong wind-driven offshore trans port near the southern extremity of the Indian Subcontinent. Effects of relatively mild austral summer upwelling that occurs in certain coastal ecosystems of the southern hemi sphere may be suppressed by the effects of intense onshore transport impacting these areas during the opposite (SW Monsoon) period. An explanation for the extreme paucity of fish landings, as well as for the unusually high production of oceanic (tuna) fisheries relative to coastal fisheries, is sought in the extremely dissipative nature of the physical systems of the region. In this respect, it appears that the Gulf of Aden and some areas within the Mozambique Channel could act as important retention areas and sources of i "see6stock" for maintenance of the function and dillersitv of the lamer reoional biolooical , !I ecosystems. 103 104 large Marine EcosySlIlms ofthe Indian Ocean - . Introduction The western Indian Ocean is the site ofsome of the most dynamically varying-. large marine ecosystems (LMEs) that exist on our planet. -
ICELAND, WHALING and ECOSYSTEM - BASED FISHERY MANAGEMENT
ICELAND, WHALING and ECOSYSTEM - BASED FISHERY MANAGEMENT PETER CORKERON Iceland, whaling and ecosystem-based fishery management. Peter Corkeron Ph.D. http://aleakage.blogspot.com/ 1 Introduction Icelanders look to the sea, and always have. Fishing has always been important to them, and they have a good record of attempting to ensure that their fisheries are sustainable. As the Icelandic Ministry of Fisheries stated in a declaration on 17th October 2006, “The Icelandic economy is overwhelmingly dependent on the utilisation of living marine resources in the ocean around the country. The sustainability of the utilisation is therefore of central importance for the long-term well being of the Icelandic people. For this reason, Iceland places great emphasis on effective management of fisheries and on scientific research on all the components of the marine ecosystem. At a time when many fish stocks around the world are declining, or even depleted, Iceland's marine resources are generally in a healthy state, because of this emphasis. The annual catch quotas for fishing and whaling are based on recommendations by scientists, who regularly monitor the status of stocks, thus ensuring that the activity is sustainable.”. Fisheries account for approximately 40% of the value of Iceland’s exported goods and exported services, and roughly two-thirds of Iceland's exported goods, minus services. Fisheries and fish processing account for little under 10% of Iceland’s Gross Domestic Product (GDP), down from more than 15% in 1980. With a population of just over 300,000 in 2007, Iceland is the world’s 178th largest nation, but in 2002 it was still ranked as the world’s 13th largest fisheries exporter. -
How Fisheries Policy Can Address Shifting Fish Stocks (PDF)
OCTOBER 2020 FS: 20-10-B FACT SHEET ON THE MOVE: HOW FISHERIES POLICY CAN ADDRESS SHIFTING FISH STOCKS Our ocean is undergoing rapid transformations due to climate change, including rising acidity, shifting currents, and warming waters.1 Fish, which are cold blooded and temperature sensitive, are responding by moving to cooler waters.2 The scale of this mass migration is striking. At least 70 percent of the commonly caught fish stocks along the U.S. Atlantic coast have shifted north or to deeper waters over the past 40 years.3 If climate change continues at its current rate, scientists predict some fish assemblages in the United States will have moved up to 1,000 miles by the century’s end.4 © OceanAdapt The distribution of Black Sea Bass biomass in 1972 and 2019. © Brenda Gillespie/chartingnature.com For more information, please contact: www.nrdc.org Lisa Suatoni www.facebook.com/NRDC.org [email protected] www.twitter.com/NRDC These changes have come so rapidly that they are outpacing For example, in less than a decade, spiny dogfish along fisheries science and policy. Climate-driven range shift the Atlantic coast went from a minor fishery to one creates a series of novel challenges for our fisheries netting 60 million pounds a year—without triggering any management system. Federal fisheries policy must adapt regulatory oversight. The result was overharvesting and and respond in order to ensure sustainability, preserve jobs, the eventual implementation of stringent catch limits that and maintain this healthy food supply. These challenges can put gillnetters and fish processors out of work.8 Likewise, be dealt with by improving federal fisheries policy in several a fishery developed seemingly overnight for a small forage specific ways: fish called chub mackerel, without any stock assessment or information on sustainable catch levels. -
Relationship Between Sagittal Otolith Size and Fish Size in Engraulis Encrasicolus and Sardina Pilchardus
EISSN 2602-473X AQUATIC SCIENCES AND ENGINEERING Aquat Sci Eng 2018; 33(3): 72-76. • DOI: 10.26650/ASE201812 Original Article Relationship between Sagittal Otolith Size and Fish Size in Engraulis encrasicolus and Sardina pilchardus (Osteichthyes: Clupeiformes) in the Southern Aegean Sea, Turkey Gökçen Bilge Cite this article as: Bilge, G. (2018). Relationship between sagittal otolith size and fish size inEngraulis encrasicolus and Sardina pilchardus (Osteichthyes: Clupeiformes) in the southern Aegean Sea, Turkey. Aquatic Sciences and Engineering, 33(3): 72-76. ABSTRACT The objective of this study was to determine the regressions between otolith size (length and height), oto- lith weight vs. fish length, and weight of European anchovyEngraulis encrasicolus (Linnaeus, 1758) (n=360) and European pilchard Sardina pilchardus (Walbaum, 1792) (n=360), living off Güllük Bay, Turkey. Fish were caught using a purse seine between January and March 2014 in the southern Aegean Sea. No differences were found between the size and weight of the left and right otoliths. Equations were used to reconstruct the original dimensions of prey from the size of hard structures found in food samples of piscivorous preda- tors living in or in the vicinity of the aquatic habitat. A linear regression model was used to determine the relationship between fish length and otolith size, whereas an exponential regression model was used to describe the relationships between lengths and weights of otoliths and fish for both species. All regressions yielded high coefficients of determination (r2) of 0.78–0.93 for E. encrasicolus and 0.80–0.95 for S. pilchardus. We conclude that otolith length and otolith weight are good indicators of the length and weight of the two species. -
Fishers' Local Ecological Knowledge (LEK) in the Atlantic Ocean (Brazil and Portugal): the Case Study of the Brazilian Sardine and the European Pilchard
Fishers' local ecological knowledge (LEK) in the Atlantic Ocean (Brazil and Portugal): The case study of the Brazilian sardine and the European pilchard Doctoral thesis in Biosciences, scientific area of Marine Ecology, supervised by Professor Miguel Ângelo do Carmo Pardal and Professor Ulisses Miranda Azeiteiro, presented to the Faculty of Sciences and Technology of the University of Coimbra Tese de doutoramento em Biociências, ramo de especialização em Ecologia Marinha, orientada pelo Professor Doutor Miguel Ângelo do Carmo Pardal e pelo Professor Doutor Ulisses Miranda Azeiteiro, apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra Heitor de Oliveira Braga Department of Life Sciences | University of Coimbra Coimbra | 2017 Funding: The present work was supported by the CAPES Foundation – Ministry of Education of Brazil for financial support (BEX: 8926/13-1) and the Centre for Functional Ecology - CFE, Department of life Sciences, University of Coimbra, Portugal. REPÚBLICA FEDERATIVA DO BRASIL “O passado também se inventa. O nosso e o dos outros. É uma das funções do presente, que não se vive à espera que o futuro nos caia dos céus, conquistado e imaginado por outros” Eduardo Lourenço Thesis Outline The thesis is structured in seven chapters: the first corresponds to the general introduction that presents the topic to be discussed in the later sections (adapted from a published book chapter), and the objectives of the thesis; four chapters with correlated themes (published or submitted for publication in scientific journals in the fields of biological sciences, marine ecology, and human ecology); a general discussion of all the findings (chapter 6) of the developed chapters; and a final chapter with the conclusion of the present investigation. -
Marine Ecology Progress Series 620:139
Vol. 620: 139–154, 2019 MARINE ECOLOGY PROGRESS SERIES Published June 18 https://doi.org/10.3354/meps12962 Mar Ecol Prog Ser Trophic ecology of range-expanding round sardinella and resident sympatric species in the NW Mediterranean Marta Albo-Puigserver 1, *, Diego Borme 2, Marta Coll 1, Valentina Tirelli 2, Isabel Palomera 1, Joan Navarro 1 1Institut de Ciències del Mar - CSIC, Barcelona 08003, Spain 2Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Trieste 34151, Italy ABSTRACT: The recent northward expansion of the round sardinella Sardinella aurita in the Mediterranean Sea has been documented as a consequence of rising sea temperature. At the same time, declines in sardine and anchovy biomass have been observed in the NW Mediterra nean Sea, necessitating an assessment of whether the expansion of round sardinella may affect sardine and anchovy populations. Here, we combined stomach content and isotopic analyses to describe the trophic habits of round sardinella in the NW Mediterranean Sea and its trophic relationships with 2 sympatric small pelagic fish, European anchovy Engraulis encrasicolus and European pilchard Sardina pilchardus . Results revealed changes in the diet of round sardinella during the year. In summer, the most important prey were copepods ( Acartia spp.) and cladocerans ( Penilia avirostris ). During winter, the diet was composed mainly of copepods and tunicates (mainly appen- dicularians), but microplankton was also numerically important in adult diets. In contrast to previ- ous studies, during spring, round sardinella principally fed on salps (Thaliacea). To our knowledge, this is the first time that salps have been identified as an important prey for round sardinella. -
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.