longline

fishing

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June 30, 2026

Quick Summary

Longlining is a commercial fishing method that uses a long main line with many baited hooks attached. There are two primary types: drifting longlines and bottom longlines.12

Drifting longlines are used to catch pelagic fish like tuna, albacore, bigeye, and bluefin tuna. They can also catch sharks, marlins, swordfish, and sailfish. These lines can extend up to 180 kilometers and require significant crew effort to set and haul.1

Bottom longlines are used to catch demersal fish, such as cod, haddock, hake, pollock, halibut, and various flatfish. The hooks on these lines may hang above the seabed to avoid bait predators. Modern advancements in automation have made longlining more efficient, allowing smaller crews to handle more hooks.2

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conservation
Surviving but threatened small populations
…or so, the growth of longline fishing, a commercial technique in which numerous baited hooks are trailed from a line that can be kilometres long (see commercial fishing: Drifting longlines; Bottom longlines), has caused many seabirds, including most species of albatross, to decline rapidly in numbers. Albatrosses follow longlining ships…
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…or so, the growth of longline fishing, a commercial technique in which numerous baited hooks are trailed from a line that can be kilometres long (see commercial fishing: Drifting longlines; Bottom longlines), has caused many seabirds, including most species of albatross, to decline rapidly in numbers. Albatrosses follow longlining ships…
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commercial fishing
Longliners
These tend to be larger vessels with the hooks and lines attached to a rope that is supported by floats or simply trailed. Usually there is an automatic line system whereby the hooks are baited and fish removed mechanically in what can be a…
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These tend to be larger vessels with the hooks and lines attached to a rope that is supported by floats or simply trailed. Usually there is an automatic line system whereby the hooks are baited and fish removed mechanically in what can be a…
Read More

commercial fishing
Drifting longlines
Used for tuna—especially in Japan, Taiwan, and Korea and to a limited extent in South Africa, Cuba, and Oceania—drifting longlines are particularly successful in the tropical Atlantic for big fish in depths from 60 to 250 metres. More than half the fish caught in…
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Used for tuna—especially in Japan, Taiwan, and Korea and to a limited extent in South Africa, Cuba, and Oceania—drifting longlines are particularly successful in the tropical Atlantic for big fish in depths from 60 to 250 metres. More than half the fish caught in…
Read More