Comparative Studies on Fish Diversity in the Chalan Beel Before and After Establishment of Fish Sanctuary

Abstract

A total of two years of investigation were done in Chalan beel, Tarash Upazila, Sirajganj district, where a fish sanctuary was constructed at the end of the first year, to determine the impact of the sanctuary on fisheries diversity. The monthly data is gathered through Seine net (Berjal). 43 species, including three alien species —Cyprinus carpio, the species Cyprinus carpio var specularies, and Oreochromis mossambicus—were identified from 11 orders and 18 families. The species with the greatest incidence was Puntius puntio (19.65%), which was followed by Amblypharyngodon mola (9.30%) and Colisa fasciata (9.57%). In 2020, Cypriniformes (46.67%) was the category with the most prevalent order. In 2021, the author, withers found 11 order, among these 11 orders, Cypriniformes found as dominant order (49.05%) and the rest 10 orders Cichliformes (1.25%), Siluriformes (20.80%), Clupieformes (4.17%), Anabatidiformes (19.49%), Decapoda (2.50%), Mastacembeliformes (0.17%), Synbranchiformes (0.002%), Perciformes (2.40%), Beloniformes (0.07%), Actinopterjii (0.007%), comprises respectively. The order Cypriniformes (17 species) was recorded to be the prevalent order, record keeping for 48.85% of the total order, upheld by Siluriformes (20.8%) and Anabantidaeformes (19.65%). Shannon-weiner diversity index is recorded 2.388 in 2020 before establishment of sanctuary and 2.528 is after establishment of sanctuary. On the setting up of the sanctuary, the mean value climbed to 2.53 from 2.39. The positive effects of the fish sanctuary could have improved the overall catch and biodiversity index, and they may also have been utilized to deal with the sustainable growth of fisheries diversity.