Foraging behaviour of brazilian riverine and coastal fishers : how much is explained by the optimal foraging theory?

Abstract

Optimal Foraging Theory (OFT) is here applied to analyse the foraging behaviour of Brazilian artisanal fi shers of the Atlantic coast (Itacuruçá and São Paulo Bagre villages) and of the inland Amazonian region (Jarauá and Ebenezer villages). Two OFT predictions are tested. Hypotheis1: A fi sher who travels to more distant sites should return with more fi sh, and Hypothesis 2: The further a fi sher goes, the longer s/he should stay fi shing in a patch. OFT did not explain fi shers’ behaviour (non-signifi cant regressions for coastal villages) or explain it in specifi c seasons (low water season for one Amazonian village: H1 r2=24.1; H2 r2=37.2) and in specifi c habitats (e.g., lakes and backwaters in Jarauá village, Lakes: H1 r2=13.5; H2 r2=24.0; Backwaters: H1 r2=34.4; H2 r2=46.5). The fi ndings can indicate areas or seasons that are under higher fi shing pressure, when fi shers try to get the best out of a situation without any concern about resource conservation. By knowing the variables that infl uence fi shers’ decision-making processes, management initiatives may be more fi ne-tuned to the local reality and are thus more likely to succeed.