lautnusantara.com - Fishing using a line as main component is one of the passive technique to catch a fish. Longlines and pole and line technique are the example of this fishing method. Let's dive in to know it better 

Longlines 

Longlines is a commercial fishing technique method that uses a long main line and baited hooks attached at interval via short branches lines called snoods or gangions. A snood is attached to the main line with a clip and it has a hook at the other end. Longlines are classified by where they are placed in the water column, which can be on the surface or on the bottom. The lines can also set by an anchor or left to drift. In a single main line, there can be up to hundreds or thousands baited hooks. The fishing vessel that rigged for longlining are called longliners, and it is commonly target a species like swordfish, tuna, halibut, and others. Longlines can also be modified with traps attached instead of hooks for crab fishing in deeper waters.

Longline fishing can also produce bycatch, but it is varied and depending on the lines placed. Bottom longlines have very little by catch compared to pelagic longlines. Longlines that produce bycatch are more common in fisheries that close to the surface because it can affect seabirds, sharks, and turtle to get caught. Regulation to this issue have been better in higher capacity countries where fishery managers can require specialized hooks and weights that reduce bycatch.

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Pole and Line

Pole and line fishing are using hand held or mechanically operated poles with baited hooks at the end. This fishing technique are targeting naturally schooling fish which are attracted to the surface by the use of lights or the scattering of bait. A pole and line fishing gear is consist of a barbless hook that attached to a line or string and a pole. This method of fishing commonly used to sport fisheries (angling), but also used in commercial fishing. 

The pole is usually made of wood like bamboo and increasingly of fiberglass. This fishing gear is using barbless hook and live bait to attract the fish. One of the main targeted fish is the tuna and this method is often used by fishers on the tropical countries. The crew, sometimes as many as 25 peoples, cast their rods and barbless hook into the water, the fish then attracted  by the shine lure and hook. Once it is hooked the fishermen will swings the line overhead and land the fish on the vessel deck where the fish is easily released from the barbless hook. 

The pole and line fishing that are use by traditional fishers usually catches fish individually and causing minimal bycatch so this method of fishing is considered as environmentally friendly. Even if there is bycatch, it could easily be released while still alive. It is done at the surface so no seabed damage at all.

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