Gill nets generally ensure good selectivity and low environmental impact, precisely because the mesh size of the nets is chosen based on the size of the fish to be caught. The gill nets used for small-scale artisanal fishing are rectangular in shape and vary in size. There are four types: bottom set gill nets (anchored gill net), encircling gill nets, trammel nets and combined trammel-gillnets.
The bottom-set gill nets (anchored - gill net) are nets lowered into the sea in a straight line and anchored to the seabed. Made of a single piece of net, the size of their mesh is chosen based on the target species that you want to catch.
Encircling gillnets are nets lowered into the sea in a circular manner, in order to enclose the expanses of water and catch the fish inside them. They are generally used close to the shore.
Trammel nets are fixed gill nets formed by three overlapping pieces of net with different mesh sizes: the external nets are larger-meshed, while those on the inside are smaller-meshed. Once they get past the first net, the fish are caught in the inner net. These are particularly indicated for catching species close to the seabed.
Combined trammel-gillnets are trammel nets in the lower part and gill nets in the upper part. This makes it possible to catch species near the seabed and also species in midwater.