Human – otter (Hydrictis Maculicollis) conflicts and coexistence in lake Kivu, Rwanda

Abstract

Freshwater biodiversity is believed to be more threatened than that of terrestrial and marine ecosystems. In Africa, 21% of freshwater species are threatened. Our study focused on assessing one freshwater otter species, the spotted-necked otters (Hydrictis [lutra] maculicollis) found in and around Lake Kivu, Rwanda. We aimed to explore conflicts between humans and otters to understand the nature of existing conflicts and identify other associated concerns to provide information to support conservation management strategies. The study was conducted in the sectors bordering Lake Kivu (Rubengera, Bwishyura, Mubuga, and Gishyita sectors) in Karongi district. We used a non-probability sampling method using purposive sampling of interviewees to identify and assess human-otter conflicts. To do this, we developed a semi-structured questionnaire and interviewed 26 study participants. We also used land use change detection methods to detect changes in land use and land cover on the lake shore zone over a 30-year period (1992-2022). Our interview results showed that there are prevalent conflicts between fish farmers and spotted-necked otters related to otter net damage and fish loss. Otters are trapped and killed during predation and damage to fish cages and their body parts have uses such as medicine and meat consumption. Furthermore, our analyses revealed that the otter habitat zone is under human pressure, leading to land use and land cover changes in addition to the 91 fish cages recorded during this study along the Lake Kivu shore. Overall, people’s knowledge and awareness of the ecological importance and threats to otters will be key to developing conservation strategies for spotted-necked otters. In addition, compliance with Rwandan laws regulating fishing, aquaculture, and the environment in general is a possible solution to mitigate conflicts, enhance coexistence between humans and otters, and protect otters and their habitat range. An in-depth study on the conservation status and distribution of otters in Rwanda is recommended. This suggestion stems from the findings of this study, which highlighted a notable gap in Rwandan freshwater biodiversity, particularly concerning otters