lauttimur.com - Gillnet is a passive fishing gear that look like walls of netting to catch fish, commonly in small scale fisheries. Gillnets are consist of single or double or triple netting that mounted together on the same frame ropes. The triple netting gillnets is known as trammel net. Several type of nets may be combined in one gear. These nets can be used alone or used in a large numbers which placed in line as more common. 

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Anytpe of gillnets can be hauled by bare hand if it is set in shallow or moderate depth in small scale fisheries. However, the use of net hauler is now very common in modern fishing, sometime it can be using power block too. The purpose of this gear is that the fish are gilled, entangled or enmeshed in the net walls. The fish may be caught in net in three way:  Gilled or held by mesh slipping behind the opercula; wedged or held by mesh around the body; and tangled or held by spines, teeth or other body parts without the body penetrating the nets. 

Beside the main net walls, gillnets also use small solid floats that made of plastics. The shape of the floats is mostly spherical, cylindrical or egg-shaped, and it is attached to the headrope. The bottom of the nets is attached with evenly distributed weights along the footrope. 

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Gillnets are one of the most effective fishing gear so it is closely monitored and regulated by fisheries management. The mesh size, twine strength, and net length and depth are regulated to reduce the bycatch of non-targeted species.  The regulation of gillnets mesh size is causing this net to be more size selective. Small fish will swim pass through it whereas the larger fish will be caught on the net. In order to reducing bycatch, gillnets also can be placed in the place in a selective area where the fish is expect to be abundant. This gear also can be set up in a shallower water to avoid whale getting entangled.

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