Conflitos entre pescadores e ariranhas (Pteronura brasiliensis) na Reserva de Desenvolvimento Sustentável Uacari, rio Juruá, Amazonas

Abstract

The recovery of giant otter populations, after the prohibition of hunting and restriction of the pelt trade, has resulted in more constant conflicts with fishermen. In this study, the fishermengiant otter conflict was analyzed in the Uacari Sustainable Development Reserve, where giant otters are accused of interfering with fisheries by eating (predation) and frightening the fish away (local interference), and of damaging fishing equipment (direct interference). Predation interference was analyzed by means of the diet overlap between the fish taxa (simplified Morisita index) consumed by humans and giant otters. The giant otter diet was assessed from feces samples, and the human diet through interviews. Local and direct interferences were analyzed through experimental fisheries with gillnets, comparing the capture efficiency between events with and without giant otter presence. Overlap between the human and giant otter diets in prey taxa was low (0.37) and varied seasonaly, being smaller in the low-water period (0.24) than in the high-water period (0.60), when both species tend to be more generalist. Overlap between the fish taxa consumed by the giant otters and those exploited by the commercial fisheries was small (0.34). Giant otter presence during the experimental fisheries was low (9.5%), and occurred in the high-water period. It did not interfere significantly in fish-capture efficiency. Only one case of direct interference by giant otters in the experimental fisheries was recorded. The results indicate that conflict between otters and fishermen in the study area is greater in the high-water period, when the income of the fisheries decreases naturally, but it seems to be mainly motivated by the residents' prejudice against giant otters.