ICES COOPERATIVE RESEARCH REPORT RAPPORT DES RECHERCHES COLLECTIVES NO. 194 Atlas of North Sea Fishes Based on bottom-trawl survey data for the years 1985—1987 Ruud J. Knijn1, Trevor W. Boon2, Henk J. L. Heessen1, and John R. G. Hislop3 'Netherlands Institute for Fisheries Research, Haringkade 1, PO Box 6 8 , 1970 AB Umuiden, The Netherlands 2MAFF, Fisheries Laboratory, Lowestoft, Suffolk NR33 OHT, England 3Marine Laboratory, PO Box 101, Victoria Road, Aberdeen AB9 8 DB, Scotland Fish illustrations by Peter Stebbing International Council for the Exploration of the Sea Conseil International pour l’Exploration de la Mer Palægade 2—4, DK-1261 Copenhagen K, Denmark September 1993 Copyright ® 1993 All rights reserved No part of this book may be reproduced in any form by photostat or microfilm or stored in a storage system or retrieval system or by any other means without written permission from the authors and the International Council for the Exploration of the Sea Illustrations ® 1993 Peter Stebbing Published with financial support from the Directorate-General for Fisheries, AIR Programme, of the Commission of the European Communities ICES Cooperative Research Report No. 194 Atlas of North Sea Fishes ISSN 1017-6195 Printed in Denmark Contents 1. Introduction............................................................................................................... 1 2. Recruit surveys.................................................................................. 3 2.1 General purpose of the surveys...................................................................... 3 2.2 Surveys used for theA tla s.............................................................................. 4 2.3 Gear and fishing m ethod ................................................................................. 5 2.4 Sampling and measuring ................................................................................ 7 2.5 Time period selected (1985 - 1987) 7 3. Factors affecting the distribution of North Sea fish e s............................................ 8 3.1 Physical environment...................................................................................... 8 3.2 Biological environment................................................................................... 16 3.3 Fisheries............................................................................................................. 16 4. Data presented in the A tlas................... 19 5. Limitations of the data ................................................................................................ 24 6. Accounts of the species caught in the years 1985 - 1987 ...................................... 27 7. Appendix..................................................................................................................... 254 8. Glossary .................................................................................................................... 257 9. Index of fish n a m es.......................................................................................................259 9.1 Scientific names ................................................................................................ 259 9.2 English.............................................................................................................. 261 9.3 French............................................................................................................... 263 9.4 G erm an ............................................................................................................ 264 9.5 D anish ............................................................................................................... 265 9.6 Norwegian ....................................................................................................... 266 9.7 Dutch................................................................................................................. 267 9.8 Sw edish............................................................................................................. 268 Within the text, numbers enclosed in square brackets refer to publications listed at the end of Chapter 5 (page 25) or at the end of the relevant species account. 1. Introduction The information used by fishery biologists for the secondary effects of fishing or changes in the fauna due to assessment of commercial fish stocks originates both changes in the environment. from the fishing industry itself (catch and effort data) and from surveys carried out with research vessels. Over the The Atlas is based on a series of bottom-trawl surveys last two decades these surveys have become an integral carried out in the years 1985 - 1987. Following the part of routine fish stock assessment, and the survey data, introductory chapters, which describe the methods used to which are obtained independently of the commercial collect and process the data and provide relevant fisheries, have become increasingly important in recent information on the biotic and abiotic environment, the years, owing to a general deterioration in the quality of distribution of 98 species or species groups is presented, catch statistics. together with a brief description of their biology. These 98 species (out of the 224 species known to occur in the At present, a great many surveys are conducted in the North Sea) comprise all species caught during the North Sea, mostly under the supervision of the Inter­ surveys. Distribution maps are given for summer and national Council for the Exploration of the Sea (ICES), winter and, for the more abundant species, for juvenile the world's oldest intergovernmental organization con­ and adult fish separately. cerned with marine and fishery science. Typically, survey data are routinely analysed to provide data on distribution, It must be understood that the unit used to illustrate the abundance, maturity, etc. for only a small group of com­ distribution of the different species, i.e. the number mercially exploited fish species. The general procedure caught per hour fishing, is a unit of relative abundance during a survey, however, is to sample at least the size (see also Chapter 5). A bottom trawl will never catch all distribution of all species in the catches. This has resulted the fish in its path and the efficiency of the gear differs in the accumulation of a large body of data which, for the both between and within species. Within these confines, most part, lie neglected in various databases. Few however, the authors hope that the data presented here published data on the distribution of North Sea fishes are will lead to a better understanding of the fishes of the available; these are mainly on commercial species and, North Sea. quite often, only refer to part of the North Sea [e.g. 1,2,3]. It is apparent, however, that the enormous amount Any atlas will undoubtedly have its limitations. The way of information collected during surveys is of value and in which the information is presented here was chosen by may be of considerable interest not only to fisheries the Steering Group. Some users might prefer to have the scientists, but also to a wider public. data available at different levels of aggregation or might wish to add new data, and some people have already The proposal to publish survey data in the form of an expressed their interest in obtaining the A tias data in a atlas was first discussed during the annual Statutory digitized form. These possibilities, however, fell beyond Meeting of ICES in 1988 [4], In 1989 an ICES Study the scope of the present project. Group met for three days to investigate the feasibility of the project [5] and in the same year a Steering Group was Since most of the surveys analysed here are annual formed to organize the necessary work. This Steering events, more data on the distribution of fishes become Group consisted of H.J.L. Heessen (IJmuiden, The available every year. In addition, in 1990 it was agreed Netherlands), J.R.G. Hislop (Aberdeen, United Kingdom), within ICES that there should be more international T.W. Boon (Lowestoft, United Kingdom), and W.L. coordination and standardization of national surveys, and Panhorst (ICES Secretariat). It was originally expected it was decided that for a period of five years starting in that most of the data would be extracted at the ICES 1991, the North Sea, Skagerrak, and Kattegat would be Secretariat, but for logistic reasons the analyses were done surveyed with bottom trawls on a quarterly basis [ 6 ]. This at the fisheries research institutes in IJmuiden and programme, the International Bottom Trawl Survey, Lowestoft. W.L. Panhorst, therefore, only participated in should considerably increase our knowledge of fish the 1989 meeting. In addition to the Steering Group, R.J. distribution and migration, and should eventually form Knijn worked on the Atlas at the IJmuiden Institute the basis of a revised and expanded Atlas of North Sea during most of 1991 (funded by the Dutch Government) Fishes. and 1992 (funded by the Commission of the European Communities, as part of the FAR programme). The Steering Group held two brief meetings (on 7 and 8 May Acknowledgements 1991 in Lowestoft and from 29 April to 1 May 1992 in IJmuiden), but most of the work was done by corres­ Many people have in one way or another contributed to pondence. the realization of this A tlas , and the authors wish to thank them for their cooperation. First of all the crews of The main objective of the Atlas of North Sea Fishes is to the various