A study on the trend of sports fishery of Mafia Island (Tanzania) along the East African coast from 1961-1972

Mafia waters in the western Indian Ocean on the east coast of Africa is a natural attractive area for fishing. It has extensive coral beds which harbour good fish life and attracts sport fishery in the area. About 12 commercially important fishes listed are caught by sports fishermen. The data indicates that this area can become an attractive centre for sports fishery almost throughout the year with peak season from November to February. Long-term planning of the fishery is necessary. The conservation measures should be evolved and gan fishing, dynamiting or any other kind of distructive fishing should be prohibited. This area has natural potential to become a sports fishing centre in the future and a great attraction for tourists and anglers.

Charts of Maryland oyster survey, 1906-1912

Historical survey maps of Maryland oyster bars, crab bottoms, and clam beds, by county and watershed. PDF includes two index maps and forty-two survey maps scanned from microfilm.

Fisheries Department Annual Report 1972

I am particularly happy to write this short forward introducing the report of the Fisheries Department for the year 1972. The Fisheries Department of the Ministry of Animal Resources is responsible for directing the development, utilization and scientific management of the fisheries resources of Uganda. This ensures that our people continue to benefit from this resource not only as a revenue earner but also as a constant source of the much needed animal protein.

Avaliaçāo preliminar do estado da exploraçāo de Kapenta (Limnothrissa miodon, Boulenger 1906), em cahora bassa com base em dados históricos de captura e esforço de 1995-2000

The fishing of kapenta (Limnothrissa miodon, Boulenger 1906) on the Cahora Bassa Dam started around 1992, when considerable stocks of this species were discovered in the lake. The species is believed to have successful established in the Dam following a natural introduction through a downstream movement from Kariba dam where it was introduced in 1967/68. Fisheries statistics on the kapenta fishery have been collected since 1993 by the Ministry of Fisheries through the Provincial Offices for Fisheries Administration of Tete (SPAP - Tete) but only data from 1995 onward are available on the database of the Ministry of Fisheries and these are the data that was used for compiling the present report on which trends of fishing effort, catch and CPUE are analyzed. Catch and effort have increased with time, from a minimum of the 4 thousand metric tons for an annual fishing effort of 36 fishing rigs in 1995 to a maximum of 12 tons for a fishing effort of 135 rigs while CPUE followed a decreasing trend during the same period. Correlation analysis between catch and effort suggests that probably environmental factors may have influence on catch variation than the increase on fishing effort. Two models were applied for calculating MSY and FMSY resulting in two pairs of roof leading to two scenario of fisheries management. 10137 tons and a FMSY of 177 fishing rigs were computed using Schaefer model while 11690 tons and a FMSY of 278 were obtained using Fox model. Considering the differences between the two results and considering the fact that the two models have no differences in terms of precision and the fact that their determination coefficient are not different it is suggested, using the precautionary principle that result from Schaefer model be a adopted for fisheries management purpose.

East African Freshwater Fisheries Research Organization Annual Report 1972

Feeding habits of many animals have been used widely in animal classifications. This is so, because the type of diet an organism requires demands structural specialisation which will utilise the available resource. Many animals may however have many structural modifications to enable them to be described as omnivourous or generalised feeders such as H. empodisma and H. riponianus (GREENWOOD 1960) which may show varying degrees of structural and adaptational intermediacy between two trophic groups. Generally, however, the diet of many animals including fish changes as the animal grow larger. The change in structural modifications is usually correlated with changes in the diet. In fishes the change may involve change from tricuspid to biscuspid and finally to unicuspid type of teeth. The degree of modification in the structure depends on the diet, thus Haplochromis that feeds on soft tissues of snails only requires modifications in oral dentition while Haplochromis that feeds on both soft tissues and shells of snails require modification in the lower pharyngeal bone for grinding purposes. Other modifications connected with food utilisation may be located in the alimentary canal. (I) The fish species that are commercially exploited are Protopterus aethiopicus, Clarias mossambicus, Tilapia esculenta, Tilapia amphimelas and Tilapia hybrids. The other fish species present in the lake but not commercially exploited are: Gnathonemus sp. Alestes sp. Labeo sp., Barbus paludinoses, Barbus jacksoni, Barbus lineomaculatus, Barbus regersi, Leptogrlanis sp., Schilbe sp., Haplochromis spp. and Hemihaplochromis sp. (2) Protopterus sp. and Clarias sp. are mostly caught with hooks on long lines. There has been a steady increase in number of hooks on the lake. Since the stocks of Protopterus and C/arias in the lake have a limit, we should control the number of hooks used by each of the fishermen in order to avoid overharvesting. (3) All the previous studies on Lake Kitangiri fisheries suggested the use of gill nets with mesh size greater than 88.9 mm in order to avoid the capture of immature Ti/apia spp. But if the fishermen are to obtain economic gains from the fishery, the optimum mesh size for use is 88.9 -101.6 mm. (4) The gillnet is a passive gear with very beneficial selective characteristics. Unfortunately the drive-in fishery which exists on Lake Kitangiri more or less destroys the gillnet selectivity characteristics. It is therefore recommended that the beating of water with poles be discouraged and stopped. (5) There is need for provision of stable fishing canoes to replace the unstable bottle palm dug-out canoes which are currently being used and which are very risky to operate. (6) The fish processing facilities on Lake Kitangiri are still inadequate. Most of the fish is sun dried, Since sun drying is very difficult during the rainy season, most fishermen carry out intensive fishing during the dry season, Concentrating most of the fishing effort in anyone season instead of spreading evenly this effort over the whole year could damage the age structure of the exploitable stocks. (7) There are considerable fluctuations in the volume of water of the lake. The feasibility of regulating the water loss through the effluent Sibiti river should be investigated by the Water Development Department. (8) Damming the Sibiti river is an expensive undertaking and therefore, the Rural Development Bank of Tanzania should be asked to assess the economic feasibility of such a project.

Semblanzas Ictiológicas Iberoamericanas: Walter Alfredo Gill Morlis

A través de esta nueva serie tratamos de conocer diferentes aspectos personales de los integrantes de la comunidad ictiológica iberoamericana. Esta iniciativa, comparte el espíritu y objetivo de las semblanzas nacionales buscando informalmente otro punto de unión en la “comunidad de ictiólogos iberoamericanos”. Quizás esté equivocado en mi apreciación, pero creo que vale la pena este intento, ya que, con la colaboración generosa e insoslayable de los integrantes de este “universo”, señalaremos un registro en el tiempo de la Ictiología Neotropical.