1. INTRODUCTION by Patrizia Jereb, Clyde F.E
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Cephalopods of the World 1 1. INTRODUCTION by Patrizia Jereb, Clyde F.E. Roper and Michael Vecchione ith the increasing exploitation of finfish resources, possibly useful to mankind, regardless of their current Wand the depletion of a number of major fish stocks commercial status. For example, this work should be useful that formerly supported industrial-scale fisheries, for the ever-expanding search for development and increasing attention continues to be paid to the so-called utilization of ‘natural products’, pharmaceuticals, etc. ‘unconventional marine resources’, which include numerous species of cephalopods. Cephalopod catches The catalogue is based primarily on information available in have increased steadily in the last 30 years, from about published literature. However, yet-to-be-published reports 1 million metric tonnes in 1970 to more than 3 million tonnes and working documents also have been used when in 2001. This increase confirms a potential development of appropriate, especially from geographical areas where a the fishery predicted by G.L. Voss in 1973, in his first large body of published information and data are lacking, general review of the world’s cephalopod resources and we are particularly grateful to colleagues worldwide prepared for FAO. The rapid expansion of cephalopod who have supplied us with fisheries information, as well as fisheries in the decade or so following the publication of bibliographies of local cephalopod literature. Voss’s review, meant that a more comprehensive and updated compilation was required, particularly for The fishery statistics presented herein are taken from the cephalopod fishery biologists, zoologists and students. The FAO official database, FISHSTAT, now available on the FAO Species Catalogue, ‘Cephalopods of the World’ by Worldwide web (FISHSTAT Plus 2000). This information is C.F.E. Roper, M.J. Sweeney and C.E. Nauen was published supplemented by field observations made by the authors in in 1984 to meet this need. many parts of the world, both in preparation of the 1984 volume, as well as for the current edition. These field visits The number of cephalopod species that enter commercial provided opportunities to examine fresh material at landing fisheries has continued to grow significantly since 1984, as sites, markets and laboratories, as well as to obtain a result of a still-growing market demand and the expansion first-hand information about local cephalopod fisheries from of fisheries operations to new fishing areas and to deeper regional fisheries workers. waters. It has been suggested that the cephalopod ‘life-strategy’ may guarantee survival against During the 20-plus years separating the two editions, the environmentally stressful conditions, including those rapid development of cephalopod fisheries worldwide and caused by heavy fishing. However, as cephalopod fisheries the simultaneous increase in the population of fisheries experienced further extensive development, parallel scientists, their research and publications, made available concern developed regarding potential overexploitation. an enormous amount of new data and research results. Thus, a broad consensus developed among fishery Sometimes it is difficult to evaluate the reliability of biologists to apply the experience gained from errors made published data, especially with regard to the identification of in finfish management to avoid possible failures in species in areas where the cephalopod fauna has not been cephalopod exploitation. To help prevent potential failures, sufficiently studied. It is entirely understandable that field refined species identification capabilities are required, as workers isolated from good library and museum/collection well as a more detailed and accurate compilation of facilities have difficulties in correctly identifying the species information on cephalopod species, distribution, biology, they encounter in the field. Moreover, the discovery of new fisheries and catch statistics. Consequently, FAO species, the more accurate delimitation of known species, recognized that a new edition of the ‘Cephalopods of the or even the introduction of nomenclatural changes, may World’ catalogue was needed. To achieve this expanded cause confusion and lead to the use of scientific names that goal, several authors with particular areas of specialization are incorrect by modern standards. Although great care were assembled to enhance the accuracy, coverage and was exercised to evaluate and correct such published utility of this revised catalogue. information used in the catalogue, some incorrect interpretations may have occurred. Another difficulty, in the In our attempt to make this document as comprehensive taxonomic literature especially, is that information on the and as useful as possible, the taxonomic coverage of this economic importance of species is rather scarce or of a edition of the catalogue is organized into 3 levels of interest: very general nature. Also, we may have overlooked important information published only in relevant local Level 1 : species of cephalopods currently exploited fisheries literature that is unavailable on a broader scale. All commercially and species utilized at the subsistence and of these potential difficulties, however, have been artisanal levels; significantly mitigated during the preparation of the new Level 2 : species of occasional and fortuitous interest to edition because of the availability on-line of fisheries fisheries; this includes species considered to have a databases and bibliographic search capabilities. potential value to fisheries, based on criteria such as With regard to the limitations mentioned above, we heartily edibility, suspected abundance, accessibility, marketability, request that readers who detect any errors in the etc.; information presented, or who have any additional Level 3 : species with no current interest to fisheries, which information and data that will enhance the accuracy and are listed only with the basic information available. utility of this book, please contact and inform one of the authors or the Species Identification and Data Programme The inclusion of such a wide range of species is necessary (SIDP) of the Marine Resources Service, Fisheries to provide the most comprehensive inventory of species Resources Division, Fisheries Department, FAO Rome. 2 FAO Species Catalogue for Fishery Purposes No. 4, Vol. 1 For further reading and information on cephalopod biology, (6) Size: The known mantle length (or total length in some fishery and resources, additional references and websites cases) of both males and females is provided where are listed at the end of references. possible. Sizes or measurements might not be completely comparable because they were taken mostly from 1.1 Plan of the Catalogue preserved or fixed specimens, but measurements of commercially important species often come from fresh This catalogue is organized by families and their material. Because of the elasticity of tentacles and arms appropriate genera within major cephalopod groups, then total length is not a very accurate measurement. Where alphabetically by species. both total length and mantle length are given, the respective figures do not necessarily pertain to the same specimen but Level 1, the most important species for fisheries, consists of may have been obtained from different sources. The detailed information in all 12 categories listed below. available information on the size attained by some species Level 2, which comprises those species of occasional, often is very meagre, so the maximum reported size cited fortuitous or potential interest to fisheries, consists of here might be considerably smaller than the actual whatever information is available and appropriate in the 12 maximum size. Maximum weight is given when available. categories. Level 3, those species for which there is no current interest to fisheries, consists of basic information (7) Geographical Distribution: The entire known (i.e. scientific name, size, geographical distribution, geographic range of the species, including areas of literature). The format within the species sections includes seasonal occurrence, is given in the text and shown on a the first two levels of treatment (Level 1 and Level 2) map. In cases where only scattered records of occurrence presented together. Species included in Level 3 are are available, question marks have been used to indicate presented at the end of each family. areas of suspected or unconfirmed distribution. Consequently, each major group and family is introduced (8) Habitat and Biology: The known depth range of the with general descriptive remarks, illustrations of diagnostic species and information on salinity and temperature of its features, highlights of the biology and relevance to habitat are given where available. For the sake of fisheries. The information that pertains to each species in exactness actual depth data are reported, as given in the Levels 1 and 2 is arranged by categories as follows: literature referenced. Information on biological aspects, (1) scientific name; (2) synonymy; (3) misidentifications; such as migrations, spawning seasons and areas, (4) FAO names; (5) diagnostic features with illustrations; longevity, food, and predators, is also included. (6) maximum known size; (7) geographical distribution with map; (8) habitat and biology; (9) interest to fisheries; (9) Interest to Fisheries: This paragraph gives an account (10) local names; (11) remarks and (12) literature. of the areas