Diversity of Indigenous Fish Species in Ratargul Freshwater Swamp Forest, Bangladesh

Abstract

Abstract. Understanding the biodiversity indices provide key information for the conservation and management of natural aquatic ecosystem. The present study was conducted in the Ratargul freshwater swamp forest of Bangladesh from April to October 2016 to assess the biodiversity status of indigenous fish species. A total 62 fish species comprising 28 threatened species were recorded. Cypriniformes (37.46%) was the most dominant order while Anguiliformes (0.026%) was in lest dominant. Among the identified fish species 19.98% was recorded as threatened following IUCN. The Mean Shannon-Wiener index, Margalef richness index, Pielou"s evenness index and Simpson dominance index were counted as 3.690±0.191, 9.497± 1.314, 0.971±0.003 and 0.982±0.003, respectively. In case of similarity percentages analysis, the highest number of similar species was found during July to August and the lowest during April to October. It may be concluded that Ratargul swamp forest is enriched with fish biodiversity.

Assessment of present environmental status of the Ratargul Swamp forest Sylhet

“…The presence of overloaded tourists all year round causing serious impact on the biodiversity of the forest. The previous study suggests that this area contains a large number of faunal and floral biodiversity (IUCN 2004, Das et al 2017. According to the local people, in the winter season, the number of migratory birds had decreased tremendously in the last five years (2014-2018).…”

Establishment of a fish sanctuary for conserving indigenous fishes in the largest freshwater swamp forest of Bangladesh: A community-based management approach

“…This area receives vast amount of water from the Shari-Goyain River, which is inundated by flash floods from Indian hill tracts ( Talukder et al., 2021 ). According to Das et al. (2017) , this forest ecosystem now shelters 62 indigenous fish species, including 28 threatened species.…”

“…The RSF is an ecologically protected area and a reputed tourist spot for its unique view of numerous aquatic flora and fauna. Some studies have already been conducted in the RSF considering plant diversity, aquatic faunal diversity, indigenous fish species diversity, factors affecting biodiversity, impact of ecotourism, etc ( Choudhury et al., 2004 ; Islam et al., 2016b ; Das et al., 2017 ; Jahan and Akhter, 2018 ). Those studies showed that fish diversity, as well as other ecosystem services of the forest, are in declining condition due to various manmade, natural, and government policy related drivers ( Islam et al., 2016b ).…”

“…Those studies showed that fish diversity, as well as other ecosystem services of the forest, are in declining condition due to various manmade, natural, and government policy related drivers ( Islam et al., 2016b ). However, the availability of threatened fish species in different ditches of this swamp forest reflects its ecological potential to be a suitable site for fish conservation ( Das et al., 2017 ). An ecosystem based management approach with local community participation is necessary for the sustainable utilization of the forest resources ( Islam et al., 2016b ; Das et al., 2017 ).…”

“…However, the availability of threatened fish species in different ditches of this swamp forest reflects its ecological potential to be a suitable site for fish conservation ( Das et al., 2017 ). An ecosystem based management approach with local community participation is necessary for the sustainable utilization of the forest resources ( Islam et al., 2016b ; Das et al., 2017 ). Therefore, a community managed fish sanctuary was established through the project “Techniques Adoption and Formulation of Guidelines for Sustainable Management of Haor and Beel Fisheries” in the Rangakuri Beel of the RSF, implemented by the Department of Aquatic Resource Management, Sylhet Agricultural University, Sylhet for the conservation and restoration of fish biodiversity.…”