Wadge Bank trawl fishery studies. Pt. 4. An analysis of the length frequency measurements of the sea bream (Lethrinus nebulosus) made in 1949 and 1953 to 1958

Length frequency distributions of the sea bream collected during the period 1953 to 1958 have been analysed. The increase in average sizes of the sea bream with depth suggests a movement to deeper waters with increase in size. By numbers, the sea bream is more abundant between 21 and 30 fathoms than in deeper areas. The recruitment was continuous and regular. There is no sign of entry or progression of a dominant brood throughout the period under study. Length frequency distribution shows three distinct modes. The first mode occurs regularly but does not progress beyond 40cm, recruitment being balanced by natural and fishing mortality. The other two which are not regular are probably the result of fishing outside regular areas. Short sections of “growth” lines which fit into one another when extrapolated, are evident. The larger lines obtained by extrapolation are parallel to one another. These tentative "growth lines" indicate that this species which enters the fishing grounds, when 15 cm or larger in length are exploited by the trawl fishery for a period of three to four years. This species appears to be six months old when it enters the fishing grounds and increases in length by about 37.5 cm in the next 30 months. Later growth slows down. The average size of the specimens sampled continued to get smaller from 1953 till 1957. It is shown that this reduction in size is due to increased fishing effort.

Annual Report of the Game and Fisheries Department for the period Ist July, 1957 to 30th June, 1958

This report follows the now established practice of covering the financial year although, as before, for the sake of continuity and accuracy many of the statistics refer to the calendar year. This year has again been an outstanding one in the field of research on wildlife conservation problems, and culminated in one of the largest short-term biological projects yet carried out in the Protectorate. The latter involved the removal by shooting of nearly 500 hippo from badly over-grazed areas in the Queen Elizabeth National Park, but every carcass was examined by a team of scientists, a variety of scientific data collected, and the meat disposed of for local consumption. Not one animal was wasted.

East African Fisheries Research Organization Annual Report 1958

A brief review of work carried out since the laboratory was established ten years ago will put present studies into perspective and show to what extent the aims of this organisation are being fulfilled. These aims can be simply defined under two heads: the maintenance of a watch on the commercial fisheries and original research designed to provide the necessary if these fisheries are to be exploited rationally and managed efficiently. While reference to past results, which cover a wide range of subjects, can best be made in the appropriate sections of this report, a short general statement on the Lake Victoria Fisheries may be useful. From the earliest records contained in Michael Graham's Report it was clear that even before 1929 considerable inroads had been made the stocks of fish in Lake Victoria. Some control measures were subsequently introduced which must have had a moderating effect, but so the Game Department reports continued to express concern regarding the state of the fisheries. During the last war some reduction in fishing effort occurred due to ,a shortage of nets, this afforded some respite to the fisheries, but after this period the fishing effort again increased steadily. At the present time the fishing effort is higher than it has ever been.

Annual Report of the East African Agricultural and Fisheries Research Council 1958

The annual report present activities carried out by the different organizations that make up the East African Agricultural & Fisheries Research Council which covers reports from the following Organisations: I. Report of the East African Agriculture and Forestry Research Organization 2. Report of the East African Fishery Research Organization 3. Report of the East African Marine Fisheries Research Organization 4. Report of the East African Trypanosomiasis Research Organization 5. Report of the East African Veterinary Research Organization The activities reported are for the period 1958