The Stock Assessment of the Kenyan Demersal Offshore Resources, Surveyed in the Period 1979-1980-1981 - Work Report no. 8. Project KEN/74/023 ”Offshore Trawling Survey”

Abstract

From February 1979 until June 1981 the trawler R/V Ujuzl surveyed the offshore Kenyan waters. The results of this vessel, supplemented by the results of three other trawlers, have been used for this stock assessment. The method used is the swept-area method. Three-level stratification has been applied. to all data (twelve fishing-grounds, two monsoon-period, fifteen groups of species). For the total trawlable surface of 3234 m2 (see charts 3 and 2), the total standing stock amounts to approximately 33,000 ton, the maximum sustainable yield is approximately 9,000 ton (the totals of table 4 plus the ”KUSI-area” plus the MESYATSEV-area). About half of these quantities consist of small fishes without any commercial value. The densities vary from 4.5 ton/m2 (MESYATSEV-area to 25.2 ton/m2 (stratum I). The results show further that, compared with other parts of the world, the productivity of the offshore demersal resources of Kenya is very low. A simple feasibility-study for each defined sub-area is added, showing that offshore trawling in Kenya is not profitable.