Resultados do programa experimental de fumagen de pescado

The fish smoking is a traditional process in most african countries and has been gradually improved to the light of changes in forms, techniques and materials. In Mozambique, in particular, this method is not as developed as expected, because it has more advantages in wetlands during rainy seasons, where there is no shortage of salt and in order to give a special taste to the dry fish. In many parts of the country, mainly in coastal areas, the smoking process is made manually by families: a small fire with any type of wood, close to a small amount of fish on a stick, tilted on fire in order to take smoke and heat for several hours. This process is used in the south (Inhaca Island), in central and northern regions (Beira, Nampula) and was also seen in Niassa Lake. This paper presents a program aimed at the application of existing knowledge about fish smoking process and at technology improvement.

The present-day fishery of the Uganda waters of Lake Victoria

The Uganda waters of Lake Victoria comprise an area of 28,500 square kilometres with a shore line of 2,380 kilometres extending from the Uganda/Tanzania border in the west to the Uganda/Kenya border in the east. A large part of the Uganda waters of the lake is less than 60 metres deep, waters deeper than 60 metres being on the eastern side of the lake. Thus the Uganda part of the lake is tilted towards the east. A number of rivers drain into the lake from the north and the River Nile flows out of the lake towards the Mediterranean Sea. The Ssese, Kome, Buvuma and Busoga Islands form a very distinctive feature of the lake. These are perhaps the remaining high hills which survived the drowning of the northern valleys during the formation of the lake. In fact, in T. P. O'Brien's book 'The Prehistoric Uganda Protectorate (1939)', Solmon gives a critical summary of the work on the formation of Lake Victoria and shows that the northern part of the lake has numerous drowned valleys, a feature which provides varying habitats for particular species of fish and which may have an effect on the species composition reflected in the catches in different areas along the northern shore of the lake. It is interesting to note that although Lake Victoria as a whole has a number of rivers draining into it, Halbfass (1923) calculated and found that 76 per cent of the water entering the lake is precipitation on the lake surface.

An instance of cyclonic upwelling in the southern offshore waters of Lake Victoria

Evidence is presented that cyclonic upwelling took place in the southern offshore waters of Lake Victoria on the 22nd to the 23rd March, 1969. Before this, the main upper thermocline was tilted downwards in the leeward northern half of the lake in response to the accumulation of epilimnetic water. Cyclonic upwelling might be quite common because of the frequent occurrence of storms on Lake Victoria, and probably on other tropical African lakes. However, to my knowledge, it has never been reported from any lake.