Culture Fisheries Assessment Methodology

Background

Culture fisheries are widespread and are expanding rapidly in South and Southeast Asia. These fisheries have a great potential to provide livelihoods for resource-poor sections of society and to increase significantly the production of high quality fish protein. In practice, the potential of culture fisheries is often not realised, due to the following problems: lack of appropriate management of existing culture fisheries, insufficient appraisal of culture fisheries development proposals, inefficient seed production techniques and inappropriate access rights regimes for the fishery. The was a need to develop methods for assessment of culture fisheries which integrated technical assessments with economic and socio-economic analysis.

Approach

Initially, the biological, technical and socio-economic conditions under which culture fisheries operate in the region were assessed through secondary data, site visits and rapid appraisals. Several culture fisheries were selected for in-depth study, with catch, limnological and some socio-economic data collected and consultation with communal management bodies carried out in each. During the second year the effects of recommended changes and/or reasons for their non-adoption were studied.

In assessing methods and management recommendations, particular attention was paid to the following aspects: empirical study of the mortality-size relationships; methods for estimation of growth and mortality parameters; bio-economic models for culture-based and culture-enhanced fisheries. Assessment methods were tested on culture fisheries in north-east Thailand by this project, on reservoir culture fisheries in Cambodia and Vietnam by the Mekong Secretariat and on floodplain stocking experiments conducted by the Third Fisheries Project in Bangladesh.

Findings

Quantitative methods for the biological/technical assessment of culture fisheries have been developed including comparative, empirical analyses for mortality-size relationships in natural ecosystems and aquaculture. Results provide a basis for optimisation of seed size in culture fisheries, with wider relevance to design of aquaculture systems.

A transparent modelling technique for culture fisheries assessment was developed, which easily adapts to specific culture systems and data availability. A prototype software package to analyze stocking in seasonal water bodies has also been produced.

Technical/biological system models have been integrated with economic techniques of profitability, activity and investment analysis, and have been employed to assess stocking and harvesting patterns in operational culture fisheries. In this way, the benefits and costs of integrating culture fisheries with seed production have been appraised, and stocking and effort control options for developing culture fisheries evaluated.

Rapid and participatory appraisal (RRA/PRA) methods were adapted to assess resource use conflicts and distribution of benefits from culture fisheries. An RRA sequence has been developed to facilitate the rapid appraisal of key issues, without compromising the flexible and adaptive RRA and PRA approach.

Methodologies have been integrated into an appraisal framework for culture fisheries development options with a checklist of key issues that should be addressed.