gillnetting

Gillnetting is a fishing method that employs vertically oriented panels of netting to catch fish. A gill net acts as a wall of mesh suspended by floats at the surface and weights on the seabed; the net is set across the path of fish so that individuals attempting to swim through become entangled by their gills, body, or fins. Net sizes and materials vary by region and target species.

Nets may be deployed as anchored sets or as drifting gear. Anchored gillnets are moored to the seabed and remain in place for several hours or days, while drift gillnets are released from a vessel and allowed to drift with currents. Mesh size and net height determine the species targeted and the size-selectivity of the catch.

Gillnetting is used to harvest a wide range of species, including various pelagic and demersal fishes. It is common in commercial fleets and in artisanal fisheries around the world. The method can be efficient for certain populations, but it often yields bycatch of non-target fish, turtles, dolphins, seabirds, and other wildlife.

Due to bycatch and habitat impacts, many regions regulate gillnetting through licensing, gear restrictions, seasonal closures, and protected-area designations. Mitigation measures include selective mesh designs, escape panels, time-and-area closures, acoustic deterrents for marine mammals, and better on-board handling practices to reduce post-release mortality.