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Jul-Larsen, E.; Kolding, J.; Overå, R.; Raakjær Nielsen,
J.; Zwieten, P.A.M. van (eds.). Management, co-management or no management?
Major dilemmas in southern African freshwater fisheries. 2. Case studies.
FAO Fisheries Technical Paper. No. 426/2. Rome, FAO. 2003. 271p.
ABSTRACT
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 features, 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?
The sociological papers show that the level of mobility among fishermen
- into as well as out of the fisheries sector - is considerable and this
mobility is strongly influenced by economic features external to the sector
(such as changes in the Copperbelt economy for Lakes Mweru and Kariba
or that of the South African mines for Lake Malombe). Changes in the number
of fishermen also depend on the effectiveness of the local access regulating
mechanisms found to exist in all the lakes. The moderate prevalence of
investment-driven changes in these fisheries is analysed with reference
to deficiencies in infrastructure, credit support and complex and often
unclear social relations prevailing at the local level. When occurring,
investment-driven increases are generally induced by access to external
financial sources. Finally, one paper compares fisheries regulations in
Zambia and Zimbabwe and shows how regulations in both countries -rather
than being based on data from the fisheries development - seem to reflect
certain historical concerns which have been important for the states with
regard to fish.
- How do fishing effort and environmental factors compare in their effects
on the regeneration of fish stocks?
The biological papers show that in the five lakes studied, environmental
drivers are often more significant than fishing effort in explaining changes
in fish production and the strong environmental influence is not only
restricted to cases where environmental variability is very high (e.g.
Lake Chilwa). Total yields in the multispecies and multigear fisheries
are surprisingly stable over a large range of effort levels, but changes
in species and size composition are considerable. So, in these fisheries
with small-scale operations there is limited danger in increased diversification
of fishing patterns and they are close to an overall unselective and ecologically
sound fishing pattern, highly adaptive to changing conditions. The only
case where fishing effort can be said arguably to have led to reduction
in catches is on Lake Malombe and there it is found that increased gear
efficiency is the probable cause for reduced fish stocks.
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