Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-19T12:40:55.356Z Has data issue: false hasContentIssue false

Effects of a targeted shrimp (Penaeus notialis) exploitation on fish catches in the Gambia estuary

Published online by Cambridge University Press:  15 March 2004

Raymond Laë*
Affiliation:
IRD, BP 1386, Dakar, Senegal
Jean-Marc Ecoutin
Affiliation:
IRD, BP 1386, Dakar, Senegal
Asber Mendy
Affiliation:
Fisheries Department of the Gambia, 6 Col. Muammar Ghaddafi Avenue, Banjul, The Gambia
Jean Raffray
Affiliation:
IRD, BP 1386, Dakar, Senegal
Jean-Yves Weigel
Affiliation:
IRD, BP 1386, Dakar, Senegal
Omar Sadio
Affiliation:
IRD, BP 1386, Dakar, Senegal
Ousmane Djobe
Affiliation:
Fisheries Department of the Gambia, 6 Col. Muammar Ghaddafi Avenue, Banjul, The Gambia
Get access

Abstract

Results of an annual survey of fishing activities and catches in the Gambia estuary (200 km long), carried out from June 2001 to May 2002, indicated that fishing effort targets mainly (66% of fishing trips) shrimps. As a result of the globalisation of fish markets, the fishery has become a quasi mono-exploitation of shrimp for exporting. At the opposite, fishing activities focusing on fish were low and carried out with large and medium mesh drift nets, gill nets and surrounding nets (17% of fishing trips), handlines and longlines (15%). The annual catch, estimated at 2350 tonnes for the estuarine part of the River Gambia, consisted of 1800 t of fish and 550 t of shrimp. Stownets were the most efficient gear accounting for 50% of the total production (550 t of shrimp and 600 t of fish) while other significant techniques were mainly drift nets (21%), longlines (11%) and gillnets (5%). Fish catches were composed with 55 fish species among which 16 species accounted for 90% of the annual catch. The average catch length of these first sixteen species was 295 mm, clearly demonstrating that fishing for fish was targeting large fish. The effects of the targeted shrimp exploitation resulted in a low fishing effort for fish leading to low fish landings and consequently to an under exploitation of fish resource in the Gambia estuary.

Type
Research Article
Copyright
© EDP Sciences, IFREMER, IRD, 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Albaret, J.J., 1987, Les peuplements de poissons de la Casamance (Sénégal) en période de sécheresse. Rev. Hydrobiol. Trop. 20, 291-310.
Albaret J.J., 1999, Les peuplements des estuaires et des lagunes. In: Lévêque C., Paugy D. (Eds.), Les poissons des eaux continentales africaines : Diversité, écologie, utilisation par l'homme. Edition de l'IRD, Paris, pp. 325-349.
Albaret, J.J., Simier, M., Darboe, F.S., Ecoutin, J.M., Raffray, J., Tito de Morais, L., 2004, Fish diversity and distribution in the Gambia estuary, West Africa, in relation to environmental variables. Aquat. Living Resour. 17, 35-46. CrossRef
Blaber S.J.M., 2000, Tropical estuarine fishes, Ecology, Exploitation and Conservation. Fish and Aquatic Resour. Ser. 7, Blackwell Science.
Bousso T., 1996, La pêche artisanale dans l'estuaire du Sine Saloum (Sénégal), Approches typologiques des systèmes d'exploitation. Thèse doctorat Univ. Montpellier II.
Chavance P., Ba M., Gascuel D., Vakily J.M., Pauly D., 2004, Pêcheries maritimes, Ecosystèmes et Sociétés en Afrique de l'Ouest : Un demi-siècle de changement. Actes du symposium international, Dakar (Sénégal), 24-28 juin 2002, Luxembourg, Office des publications officielles des Communautés européennes.
Cleveland, W.S., 1979, Robust locally weighted regression and smoothing scatterplots. J. Am. Stat. Assoc. 74, 829-836. CrossRef
Diadhiou A., Bastie F., Niang S., 1986, La pêcherie artisanale de poisson en Casamance. In: Le Reste L., Fontana A., Samba A. (Eds.), L'estuaire de la Casamance. Actes du Séminaire ISRA sur la pêche artisanale en Casamance. Ziguinchor, juin 1986, ISRA-CRODT, Dakar, pp. 111-124.
Diouf P.S., 1996, Les peuplements de poissons des milieux estuariens de l'Afrique de l'Ouest : l'exemple de l'estuaire hyperhalin du Sine Saloum. Thèses et Documents Microfichés n°156, ORSTOM, Paris.
Diouf P.S., Kébé M., Le Reste L., Bousso T., Diadhiou H.D., Gaye A.B., 1991, Plan d'action forestier, pêche et aquaculture continentales, Vol. 1, Diagnostic. Projet CRODT/MDRH/FAO, Ministère du Développement rural et de l'Hydraulique, Dakar, Sénégal.
Dorr J.A., Schneeberger P.J., Tin H.T., Flath L.E., 1985, Studies on adult, juvenile and larval fishes of the Gambia River, West Africa, 1983-1984. Report n°11, Great Lakes and Marine Waters Center international programs, The University of Michigan, Ann Arbor, Michigan.
Ecoutin J.M., Durand J.R., Laë R., Hié Daré J.P., 1994, Exploitation des stocks. In: Durand J.R., Dufour P., Guiral D., Zabi S.G.F. (Eds.), Environnement et ressources aquatiques de Côte d'Ivoire. Tome 2. Les milieux lagunaires. ORSTOM, Paris, pp. 399-444.
Ecoutin J.M., Barry M., Bouju S., Charles-Dominique E., Journet O., Penot E., Rue O., Souaré D., Sow M., 1999, Aménagement technique du milieu. In: Cormier-Salem M.C. (Ed.), Rivières du Sud, Sociétés et mangroves ouest-africaines. Edition de l'IRD, Paris, pp. 209-268.
Fisheries Department of the Gambia 1983, Frame Survey. Banjul, Gambia.
Fisheries Department of the Gambia 1997, Frame Survey. Banjul, Gambia.
Garcia, S., 1996, Stock recruitment relationships and the precautionary approach to management of tropical shrimp fisheries. Mar. Freshwater Res. 47, 43-58. CrossRef
Guiral D., Albaret J.J., Baran E., Bertrand F., Debenay J.P., Diouf P.S., Guillou J.J., Le Loeuff P., Montoroi P., Sow M., 1999, Les écosystèmes à mangrove. In: Cormier-Salem M.C. (Ed.), Rivières du Sud, Sociétés et mangroves ouest-africaines. Edition de l'IRD, Paris, pp. 63-130.
Kebe M., 1994, Étude des systèmes de production et de commercialisation dans le secteur des pêches au Sine Saloum. Doc. Scient. CRODT, 140.
King H., 1979, A review of the state of the fisheries in the Gambia. Fisheries Department, Ministry of Agriculture and Natural Resources, Fisheries Publication 32.
Lamagat J.P., Albergel J., Bouchez J.M., Descroix L., 1990, Monographie hydrologique du fleuve Gambie. ORSTOM; Organisation pour la Mise en Valeur du fleuve Gambie (OMVG), Dakar, Sénégal.
Leendertse K., 1995, Management Aspects in Estuarine Shrimp Fishing in the River Gambia. Integrated Coastal Fisheries Management in the Gambia. FI: DP/INT/91/007, Field Document 5, FAO, Rome.
Le Reste, L., 1984, Étude des variations annuelles de la production de crevettes dans l'estuaire de la Casamance (Sénégal). Etud. Rev. CGPM 61, 253-269.
Le Reste L., 1986, La pêche crevettière artisanale en Casamance. In: Le Reste L., Fontana A., Samba A. (Eds.), L'estuaire de la Casamance. Actes du Séminaire de l'Institut Sénégalais de Recherche Agronomique sur la pêche artisanale en Casamance, Ziguinchor, juin 1986, ISRA-CRODT, Dakar, Sénégal, pp. 245-256.
Le Reste, L., 1992, Variations spatio-temporelles de l'abondance et de la taille de la crevette Penaeus notialis en Casamance (Sénégal). Oceanol. Acta 4, 327-332.
Le Reste, L., 1994, Variations spatio-temporelles des prises et de la taille des crevettes Penaeus notialis dans l'estuaire sursalé du Saloum (Sénégal). Rev. Hydrobiol. Trop. 27, 129-142.
Lesack, L.F.W., 1986, Estimates of catch and potential yield for the riverine artisanal fishery in the Gambia, West Africa. J. Fish Biol. 28, 679-700. CrossRef
Lesack L.F.W., Drammeh O.K.L., 1980, Distribution of effort and structural aspects of the artisanal fishery in the Gambia. Fisheries Department, Ministry of Agriculture and Natural Resources, Fisheries Publication 33.
Lesack, L.F.W., Hecky, R.E., Melack, J.M., 1984, Transport of carbon, nitrogen, phosphorus and major solutes in the Gambia River, West Africa. Limnol. Oceanogr. 29, 816-830. CrossRef
Lhomme F., 1981, Biologie et dynamique de Penaeus (Farfante Penaeus) notialis (Perez Farfante 1967) au Sénégal. Mém. Thèse Univ. Paris 6, Paris.
Lhomme F., Garcia S., 1984, Biologie et exploitation de la crevette Penaeide au Sénégal. In: Gulland J.A., Rothschild B.J. (Eds.), Penaid shrimps: their biology and management. Fishing News Books, Farnham, UK, pp. 111-144.
Marius C., 1985, Mangroves du Sénégal et de Gambie, écologie-pédologie-géochimie- mise en valeur et aménagement. Coll. Travaux et Documents 193, ORSTOM, Paris.
Njai S.E., 2000, Traditional fish processing and marketing of the Gambia. UNU-Fisheries Training Programme, Final Project, Reykjavick, Iceland.
Reizer C., 1974, Définition d'une politique d'aménagement des ressources halieutiques d'un écosystème aquatique complexe par l'étude de son environnement abiotique, biotique et anthropique. Thèse dr., Arlon Full, 6 vol., Univ. Liège.
Ronnback, P., Troell, M., Kautsky, N., Primavera, J.H., 1999, Distribution pattern of shrimps and fish among Avicennia and Rhizophora microhabitats in the Pagbilao mangroves, Philippines. Estuar. Coast. Shelf Sci. 48, 223-234. CrossRef
Scherrer B., 1984, Biostatistique. Gaëtan-Morin Ed., Montréal, Paris.
Thayer, G.W., Colby, D.R., Hettler, W.F., 1987, Utilisation of the red mangrove prop root habitat by fishes in south Florida. Mar. Ecol. Progr. Ser. 35, 25-38. CrossRef
Vance, D.J., Haywood, M.D.E., Staples, D.J., 1990, Use of a mangrove estuary as a nursery area for postlarval and juvenile banana prawns, Penaeus merguiensis de Man, in northern Australia. Estuar. Coast. Shelf Sci. 31, 689-701. CrossRef
Welcomme R.L., 1985, River fisheries. FAO Fish. Tech. Pap. 262.