Changes in the Eastern Cape demersal inshore trawl fishery between 1967 and 1995

Abstract

Changes in the Eastern Cape demersal inshore trawl fishery operating out of Port Elizabeth over a 28-year period from 1967 to 1995 are described. The fishery is restricted to vessels operating between Slangbaai in the west to Port Alfred in the east. The principal target species are the shallow-water Cape hake and Cape horse mackerel. Eight of the more than 80 recorded species caught by the trawlers during the entire period contributed >98% to the total landed catch. These are hake, horse mackerel, panga, Agulhas sole, kingklip, Cape gumard, silver kob and chokka squid. There was a notable decline in total catch and catch rate over the period reviewed, together with considerable change in the overall catch composition. For the two time-periods for which there are accurate catch data, hake, horse mackerel and panga consistently contributed in excess of 85% to the total annual landings. There were significant decreases in the size-at-(50%) recruitment for hake, horse mackerel and panga. Although at face value it would appear that the fishery is in decline, the causative factors are largely unknown and cannot be quantified properly owing to the paucity of comparable data. The need for further detailed investigation into the population dynamics of principal species in the Eastern Cape is discussed, particularly as it pertains to spawner biomass on the Agulhas Bank.