Underwater observations of gill nets meshes

As the world, gill net fishing also constitutes an important part of Turkey's small-scale fisheries. Fishing effective of gill nets are directly related to mesh opening angle of the nets in the underwater during the fishing period. Knowing the degree of mesh opening angle of the nets in the underwater is crucial for evaluations to be made in target or non-target fishing. Today, fisheries management studies have a tendency to analyze the behavior patterns of fish species and develop suitable fishing gears accordingly. Sustainability of gill net fisheries which have been done economically important species fisheries is important for the Aegean region. Overfishing, especially on some important species, pose a risk for the continued ecological cycle. In this study, it is aimed to underwater observation the mesh openings of gill nets. Fishing efficiency of gill nets are directly related to the mesh opening of the netting, and so gill nets are often referred to by the name of fish targeted such as red mullet gill net, shrimp gill net, sole gill net, and so on. The mesh openings of gill nets can be determined mainly by the hanging ratio. However, it is known that there are some variations under operational conditions in these openings due to underwater deformations and similar reasons. Through the underwater images obtained within the scope of the project, opening angles of the gill net meshes were determined and the obtained data were discussed in terms of sustainable fisheries.