DOCSLIB.ORG

Demersal Trawling on the South African

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Demersal Trawling on the South African Benguela Dynamics Pillar, S. C., Moloney, C. L., Payne, A. I. L. and F. A. Shillington (Eds). S. Afr. J. mar. Sci. 19: 341–353 1998 1 CHANGES IN THE EASTERN CAPE DEMERSAL INSHORE TRAWL FISHERY BETWEEN 1967 AND 1995 A. J. BOOTH* and T. HECHT* Changes in the Eastern Cape demersal inshore trawl fishery operating out of Port Elizabeth over a 28-year period from 1967 to 1995 are described. The fishery is restricted to vessels operating between Slangbaai in the west to Port Alfred in the east. The principal target species are the shallow-water Cape hake and Cape horse mackerel. Eight of the more than 80 recorded species caught by the trawlers during the entire period contributed >98% to the total landed catch. These are hake, horse mackerel, panga, Agulhas sole, kingklip, Cape gurnard, silver kob and chokka squid. There was a notable decline in total catch and catch rate over the period reviewed, together with considerable change in the overall catch composition. For the two time-periods for which there are accurate catch data, hake, horse mackerel and panga consistently contributed in excess of 85% to the total annual landings. There were significant decreases in the size-at-(50%) recruitment for hake, horse mackerel and panga. Although at face value it would appear that the fishery is in decline, the causative factors are largely unknown and cannot be quantified properly owing to the paucity of comparable data. The need for further detailed investigation into the population dynamics of principal species in the Eastern Cape is discussed, particularly as it pertains to spawner biomass on the Agulhas Bank. Demersal trawling on the South African south and increased to 12, but recently market and labour-related east coasts for the Agulhas sole Austroglossus pecto- problems have resulted in the bulk of the fleet moving ralis was initiated in 1878, initially using a steam tug to Mossel Bay. off Port Elizabeth (Lees 1969). Since the late 1950s The maintenance of long-term catch records, species the South African trawler fleet has been split into two composition and length frequency data facilitates the components, an offshore (vessels operating deeper development and implementation of effective manage- than 110 m) and an inshore component (vessels < 30 m ment strategies. Unfortunately, few records were kept long and < 750 hp and restricted to an effective during the early years of the fishery, and it has only maximum fishing depth of 120 m). This distinction been since January 1967 that one of the companies provided for better control and facilitated manage- based at Port Elizabeth, at the request of the Chief ment. The inshore trawling fleet is smaller than the Directorate of Sea Fisheries, has maintained accurate offshore component and contributes c. 16% of the records. The primary objective of this study was to combined annual trawl catch (Japp et al. 1994). It also provide a description of the fishery operating from employs far fewer people and generates less revenue. Port Elizabeth, as a first step towards the possible Nevertheless, the inshore trawl fishery has, since its development of a fisheries management strategy for inception, been an important contributor to the economy the Eastern Cape within the context of a national of the Eastern Cape. management strategy for fisheries. To date, the only Currently, almost all the inshore trawling around published quantitative information on the inshore the South African coast is in the area east of Cape fishery of the Eastern Cape is contained in a paper by Agulhas and west of Port Alfred. Mossel Bay and Hecht (1977), although broader information on the Port Elizabeth are the two major ports which serve the demersal fishery of the wider South-East Coast is industry. Approximately 14% of the South African given in a number of papers, including the early one inshore trawl catch is landed at Port Elizabeth, the of Payne (1986) and the comprehensive follow-up of remainder principally at Mossel Bay. Historical Japp et al. (1994). Hecht’s (1977) paper considered records show that, by 1929, the Eastern Cape trawl the changes in the fishery during the period 1967 to fishery off Port Elizabeth had four coal-burning side- 1975. The present investigation considers the changes trawlers, which were replaced by eight diesel-powered since then in terms of the fleet, its fishing capacity, trawlers in the mid 1950s (Hecht 1976). Between species composition, catch seasonality, catch per unit 1972 and 1975 the fleet was reduced to six diesel- effort (cpue) and size-at-recruitment over the time powered side-trawlers. By the early 1980s the number periods 1967–1975 and 1985–1995 between Slangbaai of vessels operating out of Port Elizabeth had and Port Alfred. * Department of Ichthyology and Fisheries Science, Rhodes University, P.O. Box 94, 6140 Grahamstown, South Africa. Email: [email protected] Manuscript received: February 1997 2 South African Journal of Marine Science 19 1998 Fig. 1: Map of the eastern Agulhas Bank and East Coast showing the position of the study area, some of the trawling grounds, the bays closed to trawling and some of the places mentioned in text MATERIAL AND METHODS Pterogymnus laniarius collected during 1974–1975 and 1995–1996 were analysed to search for any changes in size-at-(50%) recruitment into the fishery. Catch composition, monthly catch seasonality, Cape horse mackerel Trachurus trachurus capensis annual cpue and size-at-recruitment during the periods were excluded from this analysis because it had been 1967–1975 and 1985–1995 were calculated using shown previously by Hecht (1990a) that there had data obtained from fishing companies in Port Elizabeth been a notable decrease in size-at-(50%) for the and Sea Fisheries (SF). Obtaining a comparative esti- species. Recruitment into the fishery was modelled mate of fishing effort was complicated owing to the by fitting a logistic ogive to the cumulative percentage lack of accurate data on diesel consumption and length frequency data. The logistic is of the form other parameters over the entire time-period. A simple method, modified from Punt and Japp (1994), was 1 PL = ———————δ , used in which the total annual catch was divided by –(L–L 50)/ the number of vessels operating within the fishery. 1 + exp This general fishery description index, as with other unstandardized cpue indices, does not however, where P is the percentage recruitment at length L, L δ account for, inter alia, changes in gear technology, L50 the size-at-recruitment and the steepness of the fishing strategy and skipper efficiency. ogive. The model parameters were estimated by mini- The percentage change in both annual catch and mizing the residual sum of squares (the squared average catch per vessel over the study period was difference between the observed and predicted estimated by calculating a CHANGE statistic. This percentage recruitment). statistic was computed by fitting a linear regression to the series of average catch-per-vessel, dividing the slope of the regression by the average catch-per-vessel RESULTS AND DISCUSSION for the time-period and multiplying by 100. Further- more, any significant differences between mean average catch-per-vessel for the two time-periods The fishery 1967–1975 and 1985–1995 were tested by means of a Mann-Whitney U test, because the data were found Up to approximately 1972, demersal inshore trawling to be both non-parametric and heteroscedastic. on the south-east coast of South Africa took place Length frequency data for shallow-water Cape between Cape Agulhas in the west (20°E) and East hake Merluccius capensis, Agulhas sole and panga London in the east (28°E). However, because of 1998 Booth & Hecht: Eastern Cape Demersal Fishery 3 plotters. These electronic advances have obviously contributed towards an improved fishing efficiency. Because of their size the vessels are restricted in terms of gear. Maximum fishing depth is 120 m. Most of the trawling along the coast of the Eastern Cape takes place between the 60 and the 120 m isobaths. The area fished by the inshore fleet at the eastern side of the Agulhas Bank is characterized mainly by flat grounds, both soft and hard (Japp et al. 1994). Between 1985 and 1987, many of the bays were closed to trawling, the prohibition principally because of the development of the chokka squid fishery at that time and as a consequency of concern expressed by linefishermen operating in the area. The closed areas are shown in Figure 1. Although the Eastern Cape inshore demersal trawl Fig. 2: Number of vessels operating from Port Elizabeth fishery started off directed at Agulhas sole it has, between 1967 and 1975 and between 1985 and since the early 1960s, been directed principally at 1995 hake. It was and still is a “wetfish” operation with the trawlers carrying crushed ice when they put to sea. There has been a slight decline in the duration of trips, declining catches of hake in the East London area, although the number of fishing days per month has the inshore trawl fishery of the Eastern Cape has remained fairly constant. During the period 1967–1975, since c. 1972 been operating in the area between the average duration of a trip was 10 days with a Slangbaai and Port Alfred (Fig. 1). West of Slangbaai, three-day break on shore, whereas during the period the fleet out of Mossel Bay are still very active. 1985–1995 the average trip duration was 7 days, Throughout the time-period considered here, the with one day ashore. Overall, therefore, the gear and average size and power of the side- and later modified vessel type has not changed to any great extent, which stern-trawlers in the Eastern Cape fleet has been allows for a comparison of catch and effort during 21.4 ± 3.9 m and 427.3 ± 118.7 hp respectively.
Load more

Recommended publications
  • Fronts in the World Ocean's Large Marine Ecosystems. ICES CM 2007
    - 1 - This paper can be freely cited without prior reference to the authors International Council ICES CM 2007/D:21 for the Exploration Theme Session D: Comparative Marine Ecosystem of the Sea (ICES) Structure and Function: Descriptors and Characteristics Fronts in the World Ocean’s Large Marine Ecosystems Igor M. Belkin and Peter C. Cornillon Abstract. Oceanic fronts shape marine ecosystems; therefore front mapping and characterization is one of the most important aspects of physical oceanography. Here we report on the first effort to map and describe all major fronts in the World Ocean’s Large Marine Ecosystems (LMEs). Apart from a geographical review, these fronts are classified according to their origin and physical mechanisms that maintain them. This first-ever zero-order pattern of the LME fronts is based on a unique global frontal data base assembled at the University of Rhode Island. Thermal fronts were automatically derived from 12 years (1985-1996) of twice-daily satellite 9-km resolution global AVHRR SST fields with the Cayula-Cornillon front detection algorithm. These frontal maps serve as guidance in using hydrographic data to explore subsurface thermohaline fronts, whose surface thermal signatures have been mapped from space. Our most recent study of chlorophyll fronts in the Northwest Atlantic from high-resolution 1-km data (Belkin and O’Reilly, 2007) revealed a close spatial association between chlorophyll fronts and SST fronts, suggesting causative links between these two types of fronts. Keywords: Fronts; Large Marine Ecosystems; World Ocean; sea surface temperature. Igor M. Belkin: Graduate School of Oceanography, University of Rhode Island, 215 South Ferry Road, Narragansett, Rhode Island 02882, USA [tel.: +1 401 874 6533, fax: +1 874 6728, email: [email protected]].
    [Show full text]
  • Wqg: Coastal Marine Waters
    S O U T H A F R I C A N WATER QUALITY GUIDELINES FOR COASTAL MARINE WATERS VOLUME 4 MARICULTURE Department of Water Affairs and Forestry First Edition 1995 SOUTH AFRICAN WATER QUALITY GUIDELINES FOR COASTAL MARINE WATERS Volume 4: Mariculture First Edition, 1996 I would like to receive future versions of this document (Please supply the information required below in block letters and mail to the given address) Name:................................................................................................................................. Organisation:...................................................................................................................... Address:............................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. PostalCode:........................................................................................................................ Telephone No.:................................................................................................................... E-Mail:................................................................................................................................
    [Show full text]
  • SA Wioresearchcompendium.Pdf
    Compiling authors Dr Angus Paterson Prof. Juliet Hermes Dr Tommy Bornman Tracy Klarenbeek Dr Gilbert Siko Rose Palmer Report design: Rose Palmer Contributing authors Prof. Janine Adams Ms Maryke Musson Prof. Isabelle Ansorge Mr Mduduzi Mzimela Dr Björn Backeberg Mr Ashley Naidoo Prof. Paulette Bloomer Dr Larry Oellermann Dr Thomas Bornman Ryan Palmer Dr Hayley Cawthra Dr Angus Paterson Geremy Cliff Dr Brilliant Petja Prof. Rosemary Dorrington Nicole du Plessis Dr Thembinkosi Steven Dlaza Dr Anthony Ribbink Prof. Ken Findlay Prof. Chris Reason Prof. William Froneman Prof. Michael Roberts Dr Enrico Gennari Prof. Mathieu Rouault Dr Issufo Halo Prof. Ursula Scharler Dr. Jean Harris Dr Gilbert Siko Prof. Juliet Hermes Dr Kerry Sink Dr Jenny Huggett Dr Gavin Snow Tracy Klarenbeek Johan Stander Prof. Mandy Lombard Dr Neville Sweijd Neil Malan Prof. Peter Teske Benita Maritz Dr Niall Vine Meaghen McCord Prof. Sophie von der Heydem Tammy Morris SA RESEARCH IN THE WIO ContEnts INDEX of rEsEarCh topiCs ‑ 2 introDuCtion ‑ 3 thE WEstErn inDian oCEan ‑ 4 rEsEarCh ActivitiEs ‑ 6 govErnmEnt DEpartmEnts ‑ 7 Department of Science & Technology (DST) Department of Environmental Affairs (DEA) Department of Agriculture, Forestry & Fisheries (DAFF) sCiEnCE CounCils & rEsEarCh institutions ‑ 13 National Research Foundation (NRF) Council for Geoscience (CGS) Council for Scientific & Industrial Research (CSIR) Institute for Maritime Technology (IMT) KwaZulu-Natal Sharks Board (KZNSB) South African Environmental Observation Network (SAEON) Egagasini node South African
    [Show full text]
  • PROGRAMME 4 - 7 July 2017 • Boardwalk Convention Centre • Port Elizabeth • South Africa
    SAMssPORT ELIZABETH 2017 THE 16TH SOUTHERN AFRICAN MARINE SCIENCE SYMPOSIUM PROGRAMME 4 - 7 July 2017 • www.samss2017.co.za Boardwalk Convention Centre • Port Elizabeth • South Africa Theme: Embracing the blue l Unlocking the Ocean’s economic potential whilst maintaining social and ecological resilience SAMSS is hosted by NMMU, CMR and supported by SANCOR WELCOME PLENARY SPEAKERS It is our pleasure to welcome all SAMSS 2017 participants on behalf of the ROBERT COSTANZA - The Australian National University - Australia Institute for Coastal and Marine Research at Nelson Mandela Metropolitan University and the city of Port Elizabeth. NMMU has a long tradition of marine COSTANZA has an H-index above 100 and >60 000 research and its institutional marine and maritime strategy is coming to citations. His area of specialisation is ecosystem goods fruition, which makes this an ideal time for us to host this triennial meeting. and services and ecological economics. Costanza’s Under the auspices of SANCOR, this is the second time we host SAMSS in PE and the transdisciplinary research integrates the study of theme ‘Embracing the blue – unlocking the ocean’s potential whilst maintaining social humans and nature to address research, policy, and and ecological resilience’ is highly topical and appropriate, aligning with Operation management issues. His work has focused on the Phakisa, which is the national approach to developing a blue economy. South Africa is interface between ecological and economic systems, at a cross roads and facing economic challenges. Economic growth and lifting people particularly at larger temporal and spatial scales, from out of poverty is a priority and those of us in the ‘marine’ community need to be part small watersheds to the global system.
    [Show full text]
  • TNP SOK 2011 Internet
    GARDEN ROUTE NATIONAL PARK : THE TSITSIKAMMA SANP ARKS SECTION STATE OF KNOWLEDGE Contributors: N. Hanekom 1, R.M. Randall 1, D. Bower, A. Riley 2 and N. Kruger 1 1 SANParks Scientific Services, Garden Route (Rondevlei Office), PO Box 176, Sedgefield, 6573 2 Knysna National Lakes Area, P.O. Box 314, Knysna, 6570 Most recent update: 10 May 2012 Disclaimer This report has been produced by SANParks to summarise information available on a specific conservation area. Production of the report, in either hard copy or electronic format, does not signify that: the referenced information necessarily reflect the views and policies of SANParks; the referenced information is either correct or accurate; SANParks retains copies of the referenced documents; SANParks will provide second parties with copies of the referenced documents. This standpoint has the premise that (i) reproduction of copywrited material is illegal, (ii) copying of unpublished reports and data produced by an external scientist without the author’s permission is unethical, and (iii) dissemination of unreviewed data or draft documentation is potentially misleading and hence illogical. This report should be cited as: Hanekom N., Randall R.M., Bower, D., Riley, A. & Kruger, N. 2012. Garden Route National Park: The Tsitsikamma Section – State of Knowledge. South African National Parks. TABLE OF CONTENTS 1. INTRODUCTION ...............................................................................................................2 2. ACCOUNT OF AREA........................................................................................................2
    [Show full text]
  • Status of the South African and Namibian Horse Mackerel
    Oceana Sustainability Report 2019 Status and Management of Horse mackerel in South Africa and Namibia, 2019 Capricorn Marine Environmental (Pty) Ltd David Japp, Daniel Droste and Zonke Gumede South Africa Biology and Stock Dynamics Horse mackerel (Trachurus capensis), better known as ‘maasbanker’ in the Western Cape, are similar to other Trachurus species caught globally in many other parts of the world. They are also classified as carangids which typically are game fish and fast swimmers (such as the kingfish commonly caught in the warmer waters of the South African east coast). Maasbanker, however, differ somewhat in that they are primarily filter feeders, although they do have a fairly broad diet that includes plankton and small swimming crustaceans (such as krill) and small fish and squid. What makes them a good commercial species is their shoaling behaviour, with large aggregations occurring in areas where plankton is abundant. Such is the case with the South African fishery, particularly on the east coast around the Agulhas Bank where adult maasbanker shoal and are targeted by the mid-water trawl fishery. Maasbanker are difficult to catch, as they are strong swimmers and migrate up and down in the water column and occur from the shallowest waters out to the deep waters of the continental shelf. In South Africa, the fisheries for massbanker can be broadly separated between three fishery sectors – a fishery using midwater trawls, a second using bottom trawls (typically for hake) and a third fishery targeting juvenile maasbanker using purse seine gear such as that used for sardine and anchovy. These variations, combined with the behaviour of maasbanker, require specific management interventions to ensure that the fishery remains sustainable into the future.
    [Show full text]
  • A Retrospective Analysis of Shark Catches Made by Pelagic Longliners
    OCEANOGRAPHIC RESEARCH INSTITUTE, DURBAN, SOUTH AFRICA, AFFILIATED WITH THE UNIVERSITY OF KWAZULU-NATAL A retrospective analysis of shark catches made by pelagic longliners off the east coast of South Africa and biology and life history of shortfin mako shark, Isurus oxyrinchus Submitted in fulfillment of the academic requirements for the degree of Master of Science in the Oceanographic Research Institute, affiliated with the School of Biological and Conservation Sciences, University of KwaZulu-Natal, Durban. By Alan Foulis February 2013 i i. Abstract Oceanic pelagic shark species are under threat worldwide as fishing effort increases and they are taken as both targeted and bycatch. It is widely recognized that the life history characteristics of sharks make them inherently susceptible to over- exploitation and as a result many shark-directed fisheries have collapsed. It is therefore essential that good-quality data are collected and analyzed in order to provide fisheries managers with the right information to manage these species sustainably. South Africa has a pelagic longline fishery which includes tuna-, swordfish-, and shark-directed vessels. This study analyzed logbook (1998 – 2010) and observer data (2002 – 2010) provided by the Department of Agriculture, Forestry and Fisheries in order to assess the catch composition and standardized catch-per-unit-effort (CPUE) of sharks captured as both targeted catch and bycatch. The study area consisted of four zones moving east of the 20°E meridian: the Agulhas Bank (20°E – 24°E), South Coast (25°E – 29°E), East Coast 1 (30°E – 32.8°E), and East Coast 2 (32.9°E – 36.5°E).
    [Show full text]
  • Regional Study: the Agulhas Bank Large-Scale Study: the Southern Ocean the Agulhas Bank Is the Continental Shelf South of Africa
    ROMS application south of South Africa Nicolette Changa, Pierrick Penvenb, Frank Shillingtonc and Pedro Monteiroa a Ocean Systems and Climate, CSIR, Stellenbosch, South Africa b IRD, Institut de Recherche pour le Développement, Plouzane, France c Department of Oceanography, University of Cape Town, South Africa Introduction Acknowledgements The Regional Ocean Modeling System (ROMS) is applied to Thanks to the following members of the Ocean the oceans around and south of South Africa to understand Systems and Climate Group, CSIR for the physical mechanisms that drive biological variability in the providing satellite images: region. •Nicolas Fauchereau •Sebastiaan Swart Two regions are being explored: 1. The Agulhas Bank – this regional study looks the oceanography on the shallow shelf, 2. The Southern Ocean – this includes the Indian and Atlantic sectors of the Southern Ocean. Right: Summer mean chlorophyll a concentration 1998-2007 from SeaWifs. This map shows regions of high productivity around South Africa. Regional Study: The Agulhas Bank Large-scale Study: The Southern Ocean The Agulhas Bank is the continental shelf south of Africa. It is a complex oceanic region due to its position between two diverse regimes: the strong western boundary current, the Agulhas Current, and the eastern boundary regime of the Benguela Upwelling System. The Southern Ocean region is important as a sink for atmospheric Increased productivity on the eastern Agulhas Bank is associated with the Cool Ridge- the doming of isotherms on the East carbon particularly that of anthropogenic origin. Changes to the forcing Agulhas Bank and is observed as a large tongue of cold water on the East Agulhas Bank.
    [Show full text]
  • Intrinsic Vulnerability in the Global Fish Catch
    The following appendix accompanies the article Intrinsic vulnerability in the global fish catch William W. L. Cheung1,*, Reg Watson1, Telmo Morato1,2, Tony J. Pitcher1, Daniel Pauly1 1Fisheries Centre, The University of British Columbia, Aquatic Ecosystems Research Laboratory (AERL), 2202 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada 2Departamento de Oceanografia e Pescas, Universidade dos Açores, 9901-862 Horta, Portugal *Email: [email protected] Marine Ecology Progress Series 333:1–12 (2007) Appendix 1. Intrinsic vulnerability index of fish taxa represented in the global catch, based on the Sea Around Us database (www.seaaroundus.org) Taxonomic Intrinsic level Taxon Common name vulnerability Family Pristidae Sawfishes 88 Squatinidae Angel sharks 80 Anarhichadidae Wolffishes 78 Carcharhinidae Requiem sharks 77 Sphyrnidae Hammerhead, bonnethead, scoophead shark 77 Macrouridae Grenadiers or rattails 75 Rajidae Skates 72 Alepocephalidae Slickheads 71 Lophiidae Goosefishes 70 Torpedinidae Electric rays 68 Belonidae Needlefishes 67 Emmelichthyidae Rovers 66 Nototheniidae Cod icefishes 65 Ophidiidae Cusk-eels 65 Trachichthyidae Slimeheads 64 Channichthyidae Crocodile icefishes 63 Myliobatidae Eagle and manta rays 63 Squalidae Dogfish sharks 62 Congridae Conger and garden eels 60 Serranidae Sea basses: groupers and fairy basslets 60 Exocoetidae Flyingfishes 59 Malacanthidae Tilefishes 58 Scorpaenidae Scorpionfishes or rockfishes 58 Polynemidae Threadfins 56 Triakidae Houndsharks 56 Istiophoridae Billfishes 55 Petromyzontidae
    [Show full text]
  • Global Progress in Ecosystem-Based Fisheries Management
    26th Lowell Wakefield Fisheries Symposium Global Progress in Ecosystem-Based Fisheries Management editors gordon h. kruse • howard i. browman • kevern l. cochrane diana evans • glen s. jamieson • patricia a. livingston douglas woodby • chang ik zhang university of alaska fairbanks Global Progress in Ecosystem-Based Fisheries Management editors gordon h. kruse • howard i. browman • kevern l. cochrane diana evans • glen s. jamieson • patricia a. livingston douglas woodby • chang ik zhang Alaska university of alaska fairbanks Elmer E. Rasmuson Library Cataloging in Publication Data: Global progress in ecosystem-based fisheries management / editors : G.H. Kruse … [et al.] – Fairbanks, Alaska : Alaska Sea Grant College Program, University of Alaska Fairbanks, 2012. p. : ill. ; cm. – (Alaska Sea Grant College Program, University of Alaska Fairbanks ; AK-SG-12-01) Proceedings of the symposium Ecosystems 2010 : global progress on ecosystem- based fisheries management, November 8-11, 2010, Anchorage, Alaska. Includes bibliographical references. 1. Fishery management—Congresses. 2. Sustainable fisheries—Congresses. 3. Marine ecosystem management—Congresses. I. Title. II. Kruse, Gordon H. III. Series: Lowell Wakefield Fisheries symposia series (26th : 2010 : Anchorage, Alaska). IV. Series: Alaska Sea Grant College Program report ; AK-SG-12-01. SH329.S89 P76 2012 ISBN 978-1-56612-166-8 doi:10.4027/gpebfm.2012 Citation Kruse, G.H., H.I. Browman, K.L. Cochrane, D. Evans, G.S. Jamieson, P.A. Livingston, D. Woodby, and C.I. Zhang, eds. 2012. Global Progress in Ecosystem-Based Fisheries Management. Alaska Sea Grant, University of Alaska Fairbanks. Credits This book is published by Alaska Sea Grant, supported by the U.S. Department of Commerce, NOAA National Sea Grant Office, grant NA10OAR4170097, project A/161- 02, and by the University of Alaska Fairbanks with state funds.
    [Show full text]
  • 2018 Population of Grey Gurnard In
    Population biology of grey gurnard (Eutrigla gurnardus L.; Triglidae) in the ANGOR UNIVERSITY coastal waters of Northwest Wales McCarthy, Ian; Cant, James; Marriott, Andrew Journal of Applied Ichthyology DOI: 10.1111/jai.13733 PRIFYSGOL BANGOR / B Published: 01/08/2018 Peer reviewed version Cyswllt i'r cyhoeddiad / Link to publication Dyfyniad o'r fersiwn a gyhoeddwyd / Citation for published version (APA): McCarthy, I., Cant, J., & Marriott, A. (2018). Population biology of grey gurnard (Eutrigla gurnardus L.; Triglidae) in the coastal waters of Northwest Wales. Journal of Applied Ichthyology, 34(4), 896-905. https://doi.org/10.1111/jai.13733 Hawliau Cyffredinol / General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. 27. Sep. 2021 1 Population biology of grey gurnard (Eutrigla gurnardus L.; Triglidae) in 2 the coastal waters of Northwest Wales 3 4 Running Title: Population biology of grey gurnard 5 6 I.
    [Show full text]
  • Comparison of Size Selectivity Between Marine Mammals and Commercial Fisheries with Recommendations for Restructuring Management Policies
    NOAA Technical Memorandum NMFS-AFSC-159 Comparison of Size Selectivity Between Marine Mammals and Commercial Fisheries with Recommendations for Restructuring Management Policies by M. A. Etnier and C. W. Fowler U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Marine Fisheries Service Alaska Fisheries Science Center October 2005 NOAA Technical Memorandum NMFS The National Marine Fisheries Service's Alaska Fisheries Science Center uses the NOAA Technical Memorandum series to issue informal scientific and technical publications when complete formal review and editorial processing are not appropriate or feasible. Documents within this series reflect sound professional work and may be referenced in the formal scientific and technical literature. The NMFS-AFSC Technical Memorandum series of the Alaska Fisheries Science Center continues the NMFS-F/NWC series established in 1970 by the Northwest Fisheries Center. The NMFS-NWFSC series is currently used by the Northwest Fisheries Science Center. This document should be cited as follows: Etnier, M. A., and C. W. Fowler. 2005. Comparison of size selectivity between marine mammals and commercial fisheries with recommendations for restructuring management policies. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-159, 274 p. Reference in this document to trade names does not imply endorsement by the National Marine Fisheries Service, NOAA. NOAA Technical Memorandum NMFS-AFSC-159 Comparison of Size Selectivity Between Marine Mammals and Commercial Fisheries with Recommendations for Restructuring Management Policies by M. A. Etnier and C. W. Fowler Alaska Fisheries Science Center 7600 Sand Point Way N.E. Seattle, WA 98115 www.afsc.noaa.gov U.S. DEPARTMENT OF COMMERCE Carlos M.
    [Show full text]