The shallow water trawling stations were also placed at random, and not aimed at particularly good recordings. The catches held a great variety of species, mainly small fishes. Only a few larger fishes were caught, mainly snappers (Lutjanidae) and sweetlips (Pomadasyidae). Some kingfish (Scomberomorus spp.) and large jacks (Caranx spp.) were present throughout the area. Rock cods (Epinephelus spp) were present in small numbers in many catches, mainly Epinephelus bleekeri. A giant Epinephelus tauvina of about 150 kg/2 metres was caught at Fishing Stn No. 32, south of Mafia Island.
The dominant group in the whole area was the silver bellies (Leiognathidae) of which several species were caught. Catches up to nearly a tonne of these species were made in half hour hauls in the Mafia region. A variety of mullets (Mullidae) and threadfin breams (Nemipteridae) were also taken. The mullets were generally small, but some breams were of fair size.
In the Zanzibar Channel several species of scavengers (Lethrinidae) were present in the catches, mainly the smaller species or young stages of larger types, only a few large specimens.
In the trawlable areas between coral reefs on the Channel side of Zanzibar large fishes were scarce, catches being dominated by damselfish (Pomacentridae) and other small species.
Lizardfishes, mainly brushtooth lizardfish (Saurida undosquamis) were present in fair number in most catches in shallow areas. They were generally of a smaller size than those caught in deeper waters.
The better catches were made on the Mafia Island plateau, southwards where the shelf narrows, and on the wider plateau in the north between the island and the mainland. Fishing Stn No. 33 yielded 1880 kg and Fishing Stn No. 37 gave 1190 kg.
Fairly good catches were also made on the mainland side of Zanzibar Channel, the better being taken off Bagamoyo, 980 kg and 720 kg (Fishing Stn Nos 81-82). The bulk of the larger catches was usually various silver bellies (Leiognathidae).
Of the typical pelagic community, various species of sardinella and scads constituted the main part. Sardinella sirm was the most abundant and widespread clupeoid species, and there were lesser contributions from Sardinella gibbosa, Sardinella albella and Sardinella leiogaster.
The scads were Decapterus maruadsi, Decapterus macrosoma, Decapterus kurroides and Selar crumenophthalmus. Some yellowtail scad (Atule mate) was also present, as well as a variety of the “semi-pelagic” cavallas (Carangoides spp.).
The pelagic species mentioned above also constituted the bulk of the midwater trawl catches at night over shallow grounds.
