A grid of demersal trawl stations were placed at random in the depth interval 200 - 500 metres. Effective trawling time was half an hour. Catches up to 220 kg per half hour were made. The bulk of the catch was deepwater species of the families Gempylidae, Nomeidae and Synodontidae, probably of lesser commercial value.
Off Dar-es-Salaam and south of Zanzibar Island some deepwater shrimps were caught, and also a few Nephrops and Palinurus lobsters.
It must be borne in mind that this was random trawling at positions chosen beforehand for “swept area” calculations. Fishing aimed directly at recorded concentrations may give somewhat better catches.
On the oceanic side of the islands of Mafia, Zanzibar and Pemba, and on both sides of the Pemba Channel it was difficult to find trawling ground in the depth interval 200 - 500 metres.
