Establishment and Management of Fish Sanctuary for Conserving Indigenous Fish Diversity in the Largest Freshwater Swamp Forest of Bangladesh: A Community Based Management Approach

To restore fish biodiversity and enhance fisheries production fish sanctuary is considered as an important structural management tool. Therefore, this study was conducted in the Ratargul Swamp Forest of Bangladesh to evaluate the impact of a fish sanctuary on native fish biodiversity in and around the forest ecosystem. The investigation was carried out through focus group discussions, personal interviews, and direct catch assessments during fishing by the local fishers. After two year study 65 species of indigenous fishes were recorded as 46 genera under 23 families and covering 9 orders. Cypriniformes and Cypriniidae were recorded as dominant order and family, respectively. After establishment of the fish sanctuary, a significant increasing trend of fish population was observed in the Ratargul Swamp Forest and adjacent the Shari-Goyain and the Kapna Rivers. Fish diversity indices such as Simpson dominance index (D), Shannon-Wiener diversity index (H), Margelef richness index (d) and Pielou evenness index (J) varies 0.12-0.09, 2.77-2.98, 6.15-6.14, 0.66-0.71, respectively indicated enriched species diversity and better production which might be associated with the impact of fish sanctuary establishment. Remarkably increased average fish catch was observed in the impact year (2018-19) compared to the baseline year (2019-20). Local fishers and adjacent people perceive that sanctuary is useful for protecting biodiversity, increasing fish production and helpful for improving livelihood condition of fishers and other dependent stakeholders.