Abstract

Weekly long-line trials were made from May/06 to March/07 in an estuarine system in Santa Catarina state, South Brazil, in order to implement the early stages of a long term tag/recapture program on Goliath Groupers Epinephelus itajara. Sampling design was primarily based on a previous study on local ecological knowledge of goliath grouper long-liners (e.g. baits, sampling sites and traditional long-line fishing technology), but had to be adapted to consider logistic and operational limitations of the project. The total effort was 21,500 hooks over the sampling period, however only two specimens of goliath groupers were caught, tagged and released. Several hypotheses emerged as reasonable explanations for the extremely low Capture Per Unit of Effort (CPUE), including: i) local goliath grouper population has a very low abundance in the inner bay; ii) sampling design related problems. In face of this apparent ‘failure’ of the project’s objective, we came back to local fishermen in order to find their impressions on the adequacy of the final sampling design adopted. 26 fishermen were randomly approached on 4 different local villages around the sampled areas. 90% of the interviewees affirmed that the local goliath grouper population has sensibly diminished, what was also considered as the main factor for the low CPUE. Baits used and tides on which long-lines were set were also amongst the most frequently cited inappropriate approaches. We have thus taken fishermen perceptions into account and proposed a new sampling design and a cyclic participative evaluation method that will maximize the outcomes of a national goliath grouper conservation and research project

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