Longline gear consists of a main line with many shorter lines of baited hooks trailing from it. Longliners use different sets of gear with varying hooks, bait, depth and timing to match the behavior of the species they are trying to catch.

For example, swordfish sets are shallower than tuna sets, and typically use lightsticks in addition to bait. A combination of anchors and floats can be used to fix the lines at different depths. Swordfish are usually caught during the night, while tuna is caught during the day.

In general, longline gear targets large fish. Tuna caught by longline are bigger and more valuable than the smaller fish caught in great numbers by purse seine fisheries (Hall et al., IATTC). In the Eastern Pacific, longline fishing peaks around the Marquesas Islands and near Peru (Hall et al., IATTC).

The baited hooks of a longline attract more than just the target species, including pilot whales and other cetaceans which are sometimes caught as bycatch. A growing problem with longlines is the removal of hooked fish by sperm whales, killer whales, and false killer whales. Aside from the problem of hooking the cetaceans, some fishermen have resorted to rifles and even dynamite to protect their catch.

Kinds of longline gear

• Bottom longline - the main line is anchored along the seafloor
• Pelagic longline - the main line is anchored in the water off the bottom
• Tuna set - specialized hooks and lines used specifically to catch tuna
• Swordfish set - specialized hooks and lines used specifically to catch swordfish

Examples of targeted fish

billfish, dogfish, halibut, marlin, opah, sablefish (black cod), shark, tuna and other species

[ Sources ]

    Website comments: