Review of the present state of the environment, fish stocks and fisheries of the river Niger (West Africa)

Laë R., Williams S., Morand P., Mikolasek Olivier. 2004. Review of the present state of the environment, fish stocks and fisheries of the river Niger (West Africa). In : Proceedings of the Second International Symposium on the Management of Large Rivers for Fisheries: Sustaining livelihoods and biodiversity in the new millenium. Vol. I.. Ed. by Welcomme R. and T. Petr. Rome : FAO, 199-277. (RAP Publication, 16) International symposium on the management of large river for fisheries. 2, Phnom Penh, Cambodge, 11 Février 2003/14 Février 2003.

Résumé : The Niger River is the fourth most important river in Africa. It is 4 200 km long with an estimated watershed area of 1 125 000 km2. It traverses a variety of ecological areas shared by a number of countries in the West African Region: Guinea, Mali, Niger and Nigeria for its main course; Cote d'Ivoire, Burkina Faso, Benin, Chad and the Cameroon for its tributaries. The mean annual flow is 6 100 m3 s-1. Since the beginning of the century, the Niger River has been subjected to several natural and anthropogenic perturbations: first, a very long drought period started in the 1970s when the discharges decreased strongly and the areas flooded were considerably reduced. Second, the building of dams and numerous irrigated perimeters fed by water pumping modify the hydrologic conditions of the Niger, increasing the effects of drought. These hydrological variations led to changes in the flora of the river-floodplain system and also to fragmentation or disappearance of habitats usually occupied by numerous fish species. The biological cycle of the fish that were adapted to the former hydrological cycle was modified to varying degrees, although the species richness of the river evaluated at 260 fish species did not change. Nevertheless, fish abundance changed from 1968 to 1989, fish landings declined from 90 000 metric tonnes to 45 000 metric tonnes in the central delta and large-sized species were gradually eliminated to be replaced by a sequence of small-sized and more productive species. The river is fished by dynamic and labour intensive small-scale fisheries, conducted by full and part time fishers, using diverse fishing gears adapted to various biotopes and seasonal variations in the ecosystem and the fish communities. Women play an important role in fish processing (drying or smoking fish) and marketing. In several countries around the Niger River watershed, the fish stocks have been reduced by dramatic increases in fishing activities. Aquaculture has been introduced as an accepted strategy to meet the very high demand for fish products. Aquaculture was introduced in Nigeria and Cote d'Ivoire in the 1950s based on indigenous species of tilapias and catfishes but is still in an embryonic state. The River Niger Commission was created in 1964 and evolved in 1980 into the Niger Basin Authority (NBA) to promote cooperation among the member countries and to develop its resources, notably in the field of energy, water resources, industry, agriculture, forestry exploitation, transport and communications.

Mots-clés Agrovoc : ressource halieutique, aquaculture, pêche artisanale, impact sur l'environnement, hydrologie, biodiversité, données sur les pêches

Mots-clés géographiques Agrovoc : Afrique occidentale, fleuve Niger

Classification Agris : M01 - Pêche et aquaculture - Considérations générales
M11 - Production de la pêche
M12 - Production de l'aquaculture

Auteurs et affiliations

• Laë R., IRD (SEN)
• Williams S., Obafemi Awolowo University (NGA)
• Morand P., CRH (FRA)
• Mikolasek Olivier, CIRAD-EMVT-PPA (FRA)

Source : Cirad - Agritrop (https://agritrop.cirad.fr/544038/)

Métriques

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