Synopsis of Biological Data on West African Croakers Pseudotolithus
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O 1shiesflOPS fl 3Rev. i FRm/S3! 1) (Distribution restricted) SAST - P tyiois - 1,70(37),457,O1 i seff1eg1I*Pasis -1,7O(37),57,O2 P., e1ï rtt'iis - 1,70(37),457,03 YHOPSIS CBIOLOGICAL L[A ON WES'I' RICAN CRO! ERS Pseudotolithustypus, P. senegalensis and P. elonatt Prepared by A.R. Longhurst FOOD ND AGRICULTURE ORGANIZATION OF THE U1ITFD [TIONS 'o ROME, 1969 DOCUMENTS OF THE FISHERY DOCUMENTS DE LA DIVISION DES DOCUMENTOS DELA DIRECCION RESOURCES AND EXPLOITATION RESSOURCES ET DE L'EXPLOITATION DE RECURSOS PESQUEROS Y EX- DIVISION OF FAO DEPARTMENT PES PECHES DU DEPARTMENT DES PLOTACION DEL DEPARTAMENTO OF FISHERIES PECHES DE LA FAO DE PESCA DE LA FAO Documents whicharenotofficial Des documents qui ne figurent pas Esta Subdirección publica varias se- FAO publications are issued in several parmi les publications officielles de la ries de documentos que no pueden series.They aregivenarestricted FAO sont publiés dans diverses séries. considerarse como publicacionesofi- distributionand thisfact should be Ils font seulement l'objet d'une distri- ciales de la FAO. Todos ellos tienen indicatedifthey arecited.Most of butionrestreinte,aussi convient-il de distribución limitada, circunstancia que them are prepared as working papers le préciser lorsque ces documents sont debe indicarse en el caso de ser ci- for meetings, or are summaries of infor- cités.IIs'agit le plus souvent de do- tados. La mayoría de los títulos que mationforuseofmember govern- cuments de travail préparés pour des figuranen dichas series son docu- ments,organizations,and specialists réunions, ou de résumés d'information mentos de trabajopreparados para concerned. àl'intentiondes gouvernements des reuniones o resúmenes de información pays membres, ainsi que des organi- destinados alosEstados Miembros, sations et spécialistes intéressés. Ces organizaciones y especialistasintere- séries sont les suivantes: sados. FAO Fisheries Report FR IR (No.) FAO Fisheries Circular FR IC (No.) FAO Fisheries Synopsis FR /5 (No.) Special groups of synopses are iden- Des catégories spéciales de synopses Grupos especiales de sinopsis se tified by symbols followed by classifi- sont identifiées à l'aide de symboles distinguen conlassiglassiguientes, cation numbers based on indexed code suivis des chiffres de classification ba- seguidas por números de clasificación of Current Bibliography sés surle code d'indexationdela que se basan en las claves de los ín- «Current Bibliography «: dices de la" Current Bibliography SAST Data concerning certain spe- SAST Données sur certaines espèces SAST Datos relativos a ciertas espe- cies and fish stocks. et populations de poissons. cies y poblaciones. MAST Informationon methods and MAST Renseignements sur des mé- MASTSinopsis sobre métodos y ma- subjects. thodes et des sujets. te rias. OT Oceanographic data. OT Données océanographiques. OT Sinopsis sobre oceanografía. IT Limnological data. IT Données limnologiques. IT Sinopsis sobre limnología. and et y Información sobre los recursos CART Information concerningfish- CART Renseignements sur les pêche- CART eries and resourceof certain ries et les ressources de cer- acuáticosvivosdealgunos countries and regions (FID/S). tains pays et régions (FD/S). países y regiones (FID/S). FAO FIsheries Technical Paper FR¡T (No.) Special groups of Technical Papers Des catégories spéciales de docu- Grupos especiales dedocumentos are identified by: ments techniques sontidentifiées à técnicos se identifican por las siglas l'aide des symboles suivants: siguientes: RE Indexedlistsofexperts and RE Listesindexéesd'expertset RE Listas índices de expertos y de institutions drawn from Regis- institutions tirées des registres instituciones tomadas de los ters maintained by the Fishery tenus à jour parlaDivision registros que se llevan en la Resources and Exploitation Di- des ressources et de l'exploi- Dirección de Recursos Pesque- vision. tation des pêches. ros y Explotación. CB Listes de périodiques, des sec- CB Listas de periódicos, secciones 'Current Bi- CB Listsofperiodicals,special tions spéciales de la « Current especiales de la sections of "Current Bibliogra- Bibliography for Aquatic Scien- bliography for Aquatic Scien- phy for Aquatic Sciences and ces and Fisheries «, des biblio- ces and Fisheries «, bibliogra- Fisheries,"specialbibliogra- graphiesparticulièresetdes fías especiales y trabajos rela- phies and papers concerning articles sur les problèmes de tivos a los problemas de docu- documentation problems. documentation. mentación. MFS Provisionaleditionsof "FAO MFS Editions provisoires des Ma- MFS Ediciones provisionales de los Manuals in Fisheries Science." nuels FAO de science halieu- Manualesde la FAOde tique ». Ciencias Pesqueras «. Some documents also have another IIarrive que certains documents por- Algunos documentos tienen también identification, if, for example, they have tent d'autres numéros d'identification, otra identificación si, por ejemplo, son cuyos been contributedtoa meetingfor par exemple, s'ils ont été préparés pour contribuciones a unareunión which papers have been numbered une réunion dont les documents on été documentos han sido marcados con according to another system. marqués à l'aide d'un autre système. arreglo a otros sistemas. FRm/S35 (}ev.1) SÄST - P. ty FAO Fisheries Synopsis Xo.35 Rev.I - 1,70(37),457,O1 (Distribution restricted) P0seno alensas - 1,70(37),457,02 . elongatus -1,70(37),457,03 SYNOPSIS OF BIOLOGICAL DATA ON WEST APR ICAN CROAKERS (Pseuclotolithus typus, P0 senegalerisis and P, elongatus) Propareci by A.R, LONGI{URST Institute of Marino Resources and Scr1ps Institution for Oceanography University of California San Diego FOOD AND AGRICULTURE ORGANIZATION OF TEE UNITED NATIONS Rome, November 1969 PREPARATION OF THIS SYNOPSIS A revision of the provisional version issued in October1966for presentation at the Symposium on Oceanography and. Fisheries Resources of the Tropical Atlantic, Abidjan, Ivory Coast, 20-28 October1966. The data reviewed here include some which have been published previously, some which have been included only in mimeographed reports with a limited circulation, and some previously unpublished. The author is particularly grateful to Dr. F. Williams, Director of the Guinean Trawling Survey (Joint Project19of CCTA, and latterly of OAU) for making available for inclusion hero many unpublished data. The author also wishes to thank: Mr. Bayagbona (Lagos, Nigeria) and MM. Poinsard. and Troadec (Pointe Noire, Congo Brazzaville) for MS data on their bionomio studies;M. Tixerant (Mauritania), Mrs. Cooper-Dennis (Monrovia, Liberia), Dr. Zoi and. Mr, iwei (Accra, Ghana), M. Paraiso (Dahomey), M. Marchai (Abidjan, Ivory Coast), Mr, Niven (Lagos, Nigeria), M. Lemaresquier (Cameroun), M. Magombo (Congo-Kinshasa), M. Poinsard (Pointe Noire, Congo Brazzavilie) and Sg. de Sousa e Andrade (Angola) for their ready response to a questionnaire concern- ing landing statistics. Finally, the author wishes to thank Dr, Trewavas (London, U.K.) for information on taxonomy; Prof. Th. Monod for vernacular names; and. wishes to record the assistance he received. from the late Mr, T,E. Aggo. The following abbreviations have been used in the text: GTS Guinean Trawiing Survey; CCTA Commission for Technical Co-operation in Africa; OAU Organization of African Unity; ORSTOM Office de la Roherche Scientifique et Technique Outre-mer; FFS Federal Fisheries Service of Nigeria; WAFRI ' West African Fisheries Research Institute, Distribution uCurrent Bibliography" entry FAO Department of Fisheries Longliurat, A.R,(1969) 16.-6M544 FAO Regional Fisheries Officers FAO Fish,Srnos,, (35)Rev. i :pag.var. Regional Fisheries Councils and Commissions Synopsis of biological data on West African Participants in the Abidjan Symposium croakers (Pseudotolithus P. Author senegalensis and P, elongatus) Selector SM ASE. Mauritania, Senegal. Guinea. Sierra Leone, Liberia. Ivory Coast. Ghana. Dahomey. Nigeria. Cameroor., Congo - Brazaville. Nomenclature. Taxonomy. Morphology. Distribution. Reproduction. Hybridization. Nutrition and growth, Behaviour, Population - structure, density. Exploitation - areas, gear, seasons. Protection and. management. Ci 11-22787, FRn2/S35 West African Croakers (Rev.1) CONTENTS Page No, i IDENTITY le]. 1.1 Nomenclature 1 1.11 Valid names 1 1.12 Objective synonymy 1 1.2Taxonomy 1 1,21 Affinities i 1,22 Taxonomic status 2 1.23 Subspecies 2 1,24 Standard common names,vernacular names 2 1.3 Morphology 5 1.31 terna1 morphology 5 1.32 Cytomorpho1ogy* 1.33 Protein specificity B 2 DISTRIBUTION 2l i 2.]. Total area 2,2 Differential distribution 1 2.2]. Spawn, larvae and juveniles 1 2.22Adults i 2.3 Determinants of distribution 2:2 2.4 gybridization* 3 BIONOMIOSAND LIFE HISTO 3:1 3.1 Reproàuction 1 3.11 Sexuality i 3.12 Maturity 1 3.13 Mating i 3.14 Fertilisation 1 3.15 Gonads i 3.16 Spawning i 3.17 Spawn* 3.2 Pre-adult phase* 3,3 Adult phase9 mature fish 3 3,31 Longevity 3 3.32 Hardiness 3 3.34 Predators 3.35 Parasites, diseases, injuries and abnormalities* jj FRa/835 WestAfrican Croakers (Rev.1) Page No. 3.4 Nutrition and growth 3,4 3,41 Foeding* 3,42Food. 4 3,43Growth rate 4 3,44Metabolism* 3,5Behaviour 6 3,51Migrations and. local movements* 3.52Schooling 6 3,53Responses to stimuli* 4 POPULATION 4:1 4.1 Structure 1 4,11 Sex ratio i 4.12Age composition i 4.13Size composition i 4.2Abundance and density of pou1ation 1 4,21Average abundance 1 4,22 Changes in abundance* 4,23Average density 1 4,24 Changes in density 4.3Na-tality and recruitment 2 4.31 Reproduction rates 2 4.32Factors affecting