A direct estimate of gillnet selectivity for brown trout

Abstract

Five hundred pre‐measured brown trout ( Salmo trutta ), 20 of each cm‐class from 5 to 29 inclusive, were released. They were recaptured with gillnets of mesh size 8.0, 10.5, 16.0, 19.5 and 24.0 mm, measured between adjacent knots. The nets were made of clear, nylon monofilament. The modal lengths and the general shape of the selectivity curves were in agreement with earlier findings. The height of the selectivity curve ( S ) increased exponentially with mesh size in mm ( M ): S = 0.047e 0.075M .