Standardisation des efforts de pêche des chalutiers ivoiriens et estimation de l'abondance relative dans les divers secteurs

The method developed by Robson (1966) is used to standardize fishing effort of Côte d'Ivoire trawlers whose size and power are very different. This method also allows the estimation of the relative abundances in the different fishing areas. The results obtained using 10 years data show that the entire Ivorian continental shelf can be considered as a single fishery unit. The relative fishing power of vessels is well correlated with gross tonnage, brake horse power and length of the vessel. The obsolescence of the trawlers affects their fishing power.

The biology, ecology and the fishery of Mukene, Rastrineobola argentea in Lakes Victoria, Kyoga and Nabugabo

Rastrineobola argentea, local name.s Mukene (Uganda) Omena (Kenya) and Dagaa (Tanzania) occurs in lakes Victoria, Kyoga and Nabugabo (Greenwood 1966). Until the decline of the native fishes especially the haplochromines, R. argentea was of little economic importance to the fisheries of these lakes. The stocks of this species have now increased and commercial catches on Lake Victoria account for over 30%. Fishing for R. argentea is currently still restricted to inshore areas and within the fringing islands of Lake Victoria. This fishery is not yet established on Lakes Kyoga and Nabugabo although the species is quite abundant in these lakes (Proude 1963). On moonless nights, kerosene pressure lamps are exposed on the lake to attract the fishes. These fishes are then fished out using fine meshed seine, lampara or lift nets