Thumbnail Image

Review of Tropical Reservoirs and Their Fisheries - The cases of Lake Nasser, Lake Volta and Indo-Gangetic Basin Reservoirs.

Year of publication 2011

Pages 148

Author van Zwieten, P.A.M.; Béné, C.; Kolding, J.; Brummett, R.; Valbo-Jørgensen, J., eds.;Fisheries and Aquaculture Management Division

Product type Book (series)

ISBN 9789251067413

Series title FAO Fisheries and Aquaculture Technical Papers

Series number 2070-7010|0429-3945|2070-7029|0429-9345|2070=7010 - T557

Edition 1

Synopsis (short abstract) Freshwaters contribute 15 percent of the world’s reported fish catch, or about 10.1 million tonnes in 2006, most of which comes from tropical systems. The true contribution of tropical inland fisheries is likely to be higher, as less than half of the inland capture production is actually reported. While reservoir fisheries are already an essential component of this production, the potential of most of them may even exceed their current catch levels. Opportunities exist to increase prod uctivity, provided that environmentally and socially sustainable management systems can be adopted. To realize this untapped potential, it is necessary to improve understanding of the processes influencing reservoir productivity in such a way as to involve both biological principles and stakeholder participation, as each reservoir has different properties and different research and management institutions. Seen in isolation, catch and productivity data of individual reservoirs may be difficult to interpret. The present technical paper attempts to address this issue by reviewing the knowledge accumulated in reservoirs in some very different tropical river basins: the Indus and Ganges/Brahmaputra Basin in India, the Nile River Basin in Eastern Africa and the Volta River Basin in West Africa. In particular, it focuses on many of the reservoirs of northern India and Pakistan in the Indus and Ganges systems, Lake Nasser in the Nile River and Lake Volta in the Volta R iver. Information collated from grey and published literature on the three basins is synthesized and standardized with reference to wider knowledge and up-to-date information on tropical reservoir fisheries. A considerable quantity of data and information were collected on many aspects of the systems of the three reservoirs, including hydrological, biophysical and limnological features, primary production, and fish and fisheries data. This information was condensed and synthesized wi th the aim of providing a baseline against which the ecological changes that have taken place since impoundment can be described and analysed. Efforts are made to explain changes in fish catch in relation to climatic variations, ecological succession and fishing effort. The review shows that biological data and information are generally available. However, as is also common elsewhere, all three cases suffer from the general tendency to isolate and compartmentalize research into separ ate disciplines. Usually, there is very limited cross-disciplinary flow of information or recognition of how results of various disciplines can contribute to a more comprehensive understanding of the behaviour of fish populations, human communities and ecosystems and the productive activities that depend on them. This uniform tendency severely hampered the identification of relevant management actions. A more pragmatic and holistic understanding of reservoir ecosystems is needed in order to guide the choice of indicators and the development of monitoring systems that can inform management of changes in reservoir productivity and, hence, the potential catch. The next step would be to devise a hierarchy of indicators describing the different ecological and economic processes influencing fisheries catches and to organize monitoring systems around those indicators. Only by combining information across sectoral disciplines will it be possible to reach a better unders tanding of the processes that drive fish stocks, fisheries and reservoir productivity.

Cite this content as:

van Zwieten, P.A.M.; Béné, C.; Kolding, J.; Brummett, R.; Valbo-Jørgensen, J., eds.Review of tropical reservoirs and their fisheries – The cases of Lake Nasser, Lake Volta andIndo-Gangetic Basin reservoirs.FAO Fisheries and Aquaculture Technical Paper. No. 557. Rome, FAO. 2011. 148 pp.

Language English

Also available in:
No results found.

Related items

Showing items related by metadata.

  • Thumbnail Image
    Book (series)
    Inland fisheries evolution and management
    Case studies from four continents
    2014
    Also available in:
    No results found.
    In 2009 inland fisheries produced some 10 million tonnes of fish. Despite their importance to rural communities, especially in the least developed countries. Little attention has been paid to the sector in recent years. As a result there is a deficit in management of the fisheries and also an increasing threat to freshwater by a number of non-fishery users of the aquatic resource. As part of an effort to raise awareness of the various problems facing inland fisheries and to examine more closely the various issues this document reviews four of the world's best documented inland fisheries - the Mekong, the Amazon, Lake Constance and Lake Victoria. These represent two lake fisheries and two river fisheries drawn from a wide geographical sample – Africa, Asia, South America and Europe
  • No Thumbnail Available
    Book (series)
    Inland fisheries in multiple-purpose river basin planning and development in tropical Asian countries - Three case studies 1985
    Also available in:
    No results found.
    This technical paper presents three case studies of inland fisheries in the context of a multiple-use of land and water resources in the humid tropics of Asia. Two of the three river basins are situated on islands, i.e. the Agno in the Philippines and the Mahaweli in Sri Lanka; one is on mainland Asia, i.e. the Nam Pong Basin in Thailand. Although the river basins have a number of features in common, such as, for example, their size, forest cov er and population density, they differ in a number of other environmental aspects and changes induced by the development taking place in their basins. Inland fisheries in all three catchments is represented both by capture and culture components with reservoir fisheries gaining in importance. The studies have shown that while the major constraint to the riverine fisheries has been identified as being the high level of transported sediments orig inating from eroding lands and mine waste discharge (the Agno Basin), in the reservoirs of Nam Pong and Mahaweli basins it has been the high fishing pressure, in one case non-regulated (Nam Pong), which has caused deterioration of fish stocks. Another constraint in force until recently was of a social (religious) character (Mahaweli Basin). The three studies have shown that in most situations inland fisheries can successfully devel op under conditions of the multiple use of the resource.
  • Thumbnail Image
    Book (series)
    Management, co-management or no management? Major dilemmas in southern African freshwater fisheries. Part 2: Case studies. 2003
    Also available in:
    No results found.
    This report contains ten case studies which serve as background for a synthesis report published in FAO Fisheries Technical Paper 426/1. They have been conducted in five medium sized lakes in the Democratic Republic of Congo, Malawi, Zambia and Zimbabwe. Five of the case studies focus on biological and environmental effects while the remaining five are concerned with historical and sociological analysis. In different ways all the case studies focus on some of the following three featur es, relevant for the management of freshwater fisheries in the South Africa Development Community (SADC) region: – How has fishing effort developed in these lakes over the last 50 years? Despite a considerable increase in the total fishing effort in the region, the report demonstrates great variation in effort dynamics both in time and place. Most papers distinguish between changes related to the number of people and changes in technology and investment patterns and show that most of the increases in effort have been population-driven. Only in the case of Lake Malombe have changes in effort mainly been investment-driven. – What causes the changes in fishing effort?
Show more

Users also downloaded

Showing related downloaded files

No results found.