11. RECOMMENDATIONS

The Working Group was not able to propose any precise management measure due to tne uncertainties surrounding figures for total catch and catch per unit effort. The Group agreed that unless all countries fishing in the Saharan littoral, Cape Verde and Sherbro divisions take steps to collect and report such data it will be impossible to suggest appropriate measures.

The Group therefore formulated the following recommendations to improve the situation:

1. All countries fishing in the three divisions should furnish statistical data in conformity with the CECAF statistical system (Ansa-Emmim and Levi, 1975). In this connection the Group approved the recommendations of the Third Session of the CECAF Working Group on Evaluation of Resources (Rome, 1976). In particular, the Group concluded that:

(i) all countries fishing in the three divisions should communicate their total catches properly broken down by species, divisions, fishing gear and type of vessel;

(ii) countries should communicate their statistics on effort and corresponding catches broken down by species, divisions, fishing gear and type of vessel. The Group stressed that fishing effort by pelagic trawlers should be differentiated from those of bottom trawlers. The Group agreed in general that effort should be measured more precisely by estimating the various parameters involved; and

(iii) biological data should be collected, mainly on length-frequency distributions, talking the fork length for sardinella and overall length for mackerel and horse mackerel (Ainsa-Emmim and Levi, 1975). It was decided that at least nine samples per month should be taken for each species, division and fishing gear. Sample size should be between 100 and 300. Samples should also be taken for the study of age and growth.

2. There is a need to rectify all former data on coastal pelagic stocks in the three CECAF divisions, and particularly on sardinella, mackerel and horse mackerel. Soviet and Polish scientists in particular were requested to review their data and present them with more precision concerning the estimate of fishing effort by species and by sector. It was also agreed that these data should be ready before the next meeting of the Working Group.

3. As to the measurement of fishing effort, the Group recommended that a working group of Selected scientists be called together by CECAF or under the CECAF Project to decide on the best measurements of effort in the pelagic fisheries of the three divisions: Saharan littoral, Gape Verde and Sherbro.

4. Because of present limitations in the coverage and quality of effort data, the Group approved the recommendation of the Third Meeting of the CECAF Working Group on the evaluation of resources requesting a constant monitoring of the biomass of coastal pelagic stocks using acoustic methods. CECAF or the CECAF Project were charged with promoting such studies.

5. It is necessary to continue studies on stock biology as well as on the determination of the dynamic parameters of the populations.

6. The need was stressed for cooperation among scientists of all countries, coastal or non-coastal, who have fishing interests in the three divisions, as this would enhance research activities and especially the exchange of information and standardization of methods.