Biodiversity and seasonal abundance of small indigenous fish species (SIS) in the rivers and adjacent beels of karimganj (Kishoreganj, Bangladesh)

Abstract

Small (length <25 cm) indigenous fish species (SIS) play an important role in providing animal sources of protein in the poor rural houses of Bangladesh. They are also valuable sources of vitamin A, calcium and Iron. But since the green revolution started in Bangladesh their diversity has been decreased alarmingly. This investigation was carried out from December 2010 to November 2011 in the riversand beels of Karimganj Upazila, Bangladesh to assess the biodiversity status of SIS. The samples were collected from Balikholafish landing centre and thearea was visited at least once in a month. However, during the study period, only 30 species belonging to 7 orders and 15 families were identified where 19 species had normal abundance, 6 species moderate abundance and 5 species least abundance. The highest number (9) of species was recordedfrom the family Cyprinidae and Puntius sophore being the most dominant. Among the families, contribution of Cyprinidae was 30%, followed by Bagridae and Schilbeidae 10%, Channidae and Clupeidae 6.67% and rest of the each family was 3.33%. The species comprised 39% catfishes, 22% minnows, 17% barbs, 10% perch, 5% snakeheads, 2% gourami, and river shads, loaches, gar, glass fish, goby were 1% individually. The highest number of species (25) was found in October and the lowest (3) in February. The maximum yield of SIS was found in (Sep-Dec) period and the least availability of SIS found during (Jan-Apr). Among the fish species, 2 were considered as critically endangered (CR), 4 were endangered, 3 were vulnerable (VU) and 2 were Data Deficient (DD). From this repot, general people, researcher and policy makers would be able to know about the valuable SIS fishes of the study area, their present biodiversity status and their seasonal abundance. The information will be helpful for proper conservation and management of the SIS.