Selection of multifilament trammel nets with different mesh width in Lake Erçek

This study was conducted in Lake Erçek, located in the Van Lake basin. The study examined the selectivity of multifilament trammel nets used in the fishing of pearl mullet (Alburnus tarichi, Güldenstädt, 1814) in the lake. The efficiency of nets with mesh sizes of 22 mm, 24 mm, and 26 mm was evaluated in the research. A total of 5.336 pearl mullets were caught in the study carried out between October 2021 and April 2022. 1.296, 1.721 and 2.319 fish were caught from nets with mesh sizes of 22. 24 and 26 mm, respectively. The aim of the study was to determine the most suitable mesh size for sustainable pearl mullet fishing in Lake Erçek. The Holt (1963) method was used to calculate the selectivity parameters. This method considers the fish length and mesh size to determine which size of fish can be caught by the nets. The calculations showed that nets with a 26 mm mesh size had the highest efficiency and contributed to the preservation of fish stocks by allowing smaller fish to escape. The optimum catch lengths for the 22 mm, 24 mm, and 26 mm nets were calculated as 21.15 cm, 22.47 cm, and 23.69 cm, respectively. It was particularly noted that nets with a 22 mm mesh size caught fish below the legal catch size, which could negatively affect the sustainability of the fish stocks. As a result, it was concluded that nets with a 26 mm mesh size are the most suitable option for sustainable fishing in Lake Erçek. The findings of the study provide important data for the conservation of pearl mullet stocks and for the sustainable management of fishing practices.