author(s)
Mst. Niloy Jaman, Md. Mohtasim Araf, Samir Tanjim, Md Mahfujur Rahman, Md. Lipon Mia and Md Saiful Islam

abstract
The Pyra River, a vital aquatic ecosystem, supports diverse fish assemblages that are crucial fish diversity. This study aims to evaluate the impact of fishing net selectivity and craft operations on fish assemblage dynamics in the Pyra River, with a focus on understanding the ecological consequences of these practices. A comprehensive ecological assessment was conducted over a 12-month period, during which fish assemblages were sampled using various types of fishing nets with differing mesh sizes and selectivity characteristics. The study also documented the operational patterns of fishing crafts, including the frequency, duration, and locations of fishing activities. The results revealed that fishing net selectivity significantly influenced the size and species composition of the captured fish, with smaller mesh sizes leading to higher bycatch of juvenile and non-target species. This has implications for the sustainability of fish populations, as the removal of juveniles can hinder recruitment and lead to long-term declines in fish stocks. The study highlights the need for sustainable fishing practices in the Pyra River, including the adoption of selective fishing gears that minimize bycatch and the implementation of spatial and temporal management measures to reduce the ecological impact of fishing activities.