Preliminary stock assessment for the shallow water shrimp trawl fishery of Tanzania Based on Catch and effort data for 1988.

Preliminary stock assessment for the shallow water shrimp trawl fishery of Tanzania Based on Catch and effort data for 1988.

Descripción

The assessment is based on the "swept area" method applied to the catch and effort data for 1988. The estimates of maximum sustainable yield (MSY) obtained when the trawl efficiency was assumed to be unity are 1,057 tonnes (when M = 2.4 annual), 1,232 tonnes (when M = 3.0) and 1,412 tonnes (when M = 3.6). The associated estimates for the standard fishing effort required to achieve MSY are respectively 4,859 standard days, 6,078 standard days and 7,286 standard days. These values compare with the observed catch in 1988 of 706 tonnes (whole weight) from an effort of 1,688 standard days.