Observations on gillnet catches of Kariba tilapia, Oreochromis mortimeri from Bumi Basin of Lake Kariba, Zimbabwe.

Gillnet catches of Oreochromis mortimeri (Trewavas) were studied in the Bumi Basin of Lake Kariba in 1988 and 1989. Total length (TL) was positively correlated with standard length (SL). The linear relationship between TL and SL was TL=1.91 + 1.22 SL (r super(2)=0.982). The relationship between SL and weight in g (W) was of the form W = 0.12 SL super(2.67). Maximum standard length (L sub(max)) was 33 cm and asymptotic length (L sub( infinity )) was 34.7 cm. Monthly ratios of male to female varied between 0.6:1 and 13:1. The mean ratio was 57.4% male: 42.6%female.

Not by rent alone: analysing the pro-poor functions of small-scale fisheries in developing countries

The dominant view in academic and policy arenas is increasingly one in which the major contribution of capture fisheries to development should be derived from the capacity of society to maximise the economic rent of fishery resources. Drawing upon empirical experience from the South, this article highlights the potentially disastrous consequences that a universal implementation of the rent-maximisation model would have in developing countries, and argues that a more gradual approach would be preferable.

A new bandfish, Owstonia sarmiento (Pisces: Perciformes: Cepolidae: Owstoniinae), from the Philippines with a key to species of the genus

A new bandfish, <i>Owstonia sarmiento</i>, is described from specimens collected off East Luzon, Philippines at about 200-300m depth during the AURORA 2007 Expedition. It differs from other known congeneric species in having more dorsal fin rays, two anal spines, more vertebral counts, and the least lateral row scale counts. The species is described (colour photo and radiograph included) and a diagnostic key to species of the genus is provided.

The natural history and fisheries ecology of Lake Chilwa, southern Malawi

Lake Chilwa produces between zero and 24,000 metric tons of fish per year, making it one of the most productive but variable lakes in Africa. The size of the lake varies seasonally and among years, sometimes drying completely. Its surrounding wetland and floodplain provide habitat for a diversity of birds and economically valuable grasses and reeds. When the lake has water, there is considerable activity on its shores and temporary fishing villages spring up. People move in and out of the lake basin in concert with these seasonal and longer term changes.

Most significant change (MSC)

MSC was developed by Rick Davies in the early 1990’s, primarily to address the problem of ‘how to summarise & report progress when there is a diversity of activities, not all known in advance, let alone their outcomes and a need to respect people’s judgements of what is important to them.’

Mono-and polyculture of silver barb (Puntius gonionotus) in deepwater rice systems in Bangladesh.

Experiments with fish enclosures were conducted at the Deepwater Rice Farming Systems Research Site at Shuvullah, Mirzapur, Bangladesh. The objective was to study the performance of silver barb (Puntius gonionotus) called Thai sharputi or rajputi in Bangladesh in mono-and-polyculture with grass carp (Ctenopharyngodon idella), common carp (Cyprinus carpio), catla (Catla catla) and rohu (Labeo rohita). Each enclosure measured 21 m x 21 m with an approximate net height of 3.5 m.

Microeconomics of existing aquaculture production systems: basic concepts and definitions

The paper focuses on the role of the relative prices in farmers' production behaviour and presents a model for explaining output variations among farmers. In the context of this production mode, the concepts of output elasticity, economies of scale, and technical and economic efficiency are explained using illustrative examples. The type of data used and the estimation techniques are briefly described and the distinction between average and frontier production functions is emphasized.

Measuring transaction costs of fisheries co-management in San Salvador Island, Philippines

It is generally accepted that co-management systems are more cost-effective than centralized management of natural resources. However, no attempts have been made to empirically verify the transaction costs involved in fisheries co-management. Some estimates of transaction costs of fisheries co-management in San Salvador Island, Philippines, are presented in this paper. These estimates are used to compare the various transaction costs in co-managed and in centrally managed fisheries in San Salvador Island.

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