Interactions between the Neotropical otter (Lontra longicaudis) and gillnet fishery in the southern Brazilian coast

The Neotropical otter (Lontra longicaudis) is an aquatic carnivore that interacts with fisheries activities and competes with fisherman for resources. Information about the biology and conservation issues of a species can be obtained from traditional ecological knowledge collected from the communities that share the same resources. In this sense, the objective of this study was to describe conflicts between the otters and two fishing communities (Imbé and Tramandaí) in the Tramandaí Lagoon (29°57′S; 50°11′W), in southern Brazil. We conducted 36 interviews that represented 72% of the local fishermen that use gillnets in the lagoon. All fishermen reported that otters interfered with fishing activities, by feeding on fish in the gillnets, and 75% of those interviewed reported gear damage. Fifty percent of the fishermen reported that observed the otters used the lagoon daily. Many fishermen (41.6%) also reported that the amount of damage attributed to the otters was considered “small”, but the depredation was reported as occurring daily (55.5%). Fishermen from Imbé have a more negative perception of the interaction with otters, probably because they usually fish near to the area most frequently used by otters. This amplifies the magnitude of the conflict and damage. In order to minimize the depredation of fish by otters directly on the gillnets, we suggested some measures to fishery management, as well as additional studies about the potential prey overlap between the Neotropical otter and the fishery.