Fishermen's perception of Neotropical otters (Lontra longicaudis) and their attacks on artisanal fixed fence traps: The case of caiçara communities

Abstract

In Brazil, fishermen and fish farmers have informally reported the problem of Neotropical otter (Lontra longicaudis) attacks on their gear and fish ponds. Information about these interactions can be obtained from traditional ecological knowledge. Given this context, the objective of this study was to verify the perception of ‘caiçara’ fishermen of Neotropical otters and their attacks on fixed fence traps in the Cananéia and Comprida Islands (25°00′S, 47°55′W), in the southern part of São Paulo state. We conducted 31 interviews and applied ‘participant observation’ and ‘informal conversation’ techniques. The frequencies of answers to each question were compared using non-parametric statistical tests. In total, 27 (87.10%) of the fishermen reported currently using fixed fence traps. Twenty-nine (93.55%) confirmed that predation by Neotropical otters occurred involving their fixed fence traps. A total of 22 fishermen reported the extent of the damage, and many of them (45.45%) also reported that the amount of damage attributed to the otters is considered “small.” Of the 29 (93.55%) fishermen who provided opinions about possible alternatives to reduce fixed fence trap predation, eight (27.59%) said that there are no alternatives, and 21 (72.41%) had different opinions, such as the use of a light fixture, nocturnal surveillance, the use of barbed wire on the fixed fence trap door and the use of scarecrows. Although there is a competitive relationship between ‘caiçara’ fishermen and Neotropical otters involving the use of the same space and resources, it is not harmful in terms of the possible risks affecting the survival of this mustelid. This study describes for the first time the perception by fishermen of the ‘caiçara’ communities in relation to Neotropical otters and their attacks on fixed fence traps. The information acquired from traditional ecological knowledge is an important tool in developing strategies for the management and conservation of otters.