What is pelagic trawling?

What is pelagic trawling?

Pelagic, or midwater trawls have a cone-shaped body and a closed ‘cod-end’ that holds their catch. Pelagic trawls are generally much larger than bottom trawls and can be towed by one or two boats (pair trawling). They are designed to target fish in the mid- and surface water, such as herring, hoki and mackerel.

How does midwater trawling work?

Similar to bottom trawling, midwater trawling involves towing a large net through the water column. Trawls are designed to capture and trap the target species inside the codend as the net is hauled through the water. Beam trawls consist of a cone-shaped net with a horizontal opening that narrows to the codend.

What is trawl fishing gear?

OverviewA bottom trawl is constructed like a cone-shaped net that is towed (by one or two boats) on the bottom. It consists of a body ending in a codend, which retains the catch. Normally the net has two lateral wings extending forward from the opening. The mouth of the trawl is framed by headline and groundrope.

Where does midwater trawling occur?

Target Species: Pelagic species, sometimes some demersal fish. The Gear and its Environment: Deployment Area: Midwater trawling is carried out mainly at sea, on the continental shelf, sometimes in deeper waters as well as in some lakes.

What’s the difference between trolling and trawling?

The basic difference between these two similar terms is that trawling involves a net and is typically done for commercial fishing purposes, while trolling involves a rod, reel, and a bait or lure,” and is typically done by recreational fishermen.

Why is trawling used?

Trawl nets are responsible for the greatest portion of the nation’s fish and shrimp catches. There are hundreds of trawl styles and sizes used around the world to target schooling species or groups of species. These nets often target demersal species along the seafloor or pelagic species in the water column.

Is pelagic trawling sustainable?

Environmental impact Pelagic trawls are very good at being species specific in operation. The large meshes in the mouth of the trawl will only herd shoaling species into the trawl.

What do trawl nets catch?

What do pelagic trawlers catch?

Midwater trawling catches pelagic fish such as anchovies, shrimp, tuna and mackerel, whereas bottom trawling targets both bottom living fish (groundfish) and semi-pelagic fish such as: cod, squid, halibut and rockfish.

Is trawling legal?

The Pacific and North Pacific Fishery Management Councils banned bottom trawling in more than 840,000 square miles of seafloor in the Pacific, Bering Sea, and the Arctic. The state of California banned bottom trawling for spot prawns to reduce discards and increase prawn catches for fishermen using more selective gear.

Why are pelagic trawls good for the sea?

Usually the skipper is very careful not to allow his gear to get too close to the seabed because these trawls will damage easily if the come into contact with the seabed. Pelagic trawls are very good at being species specific in operation. The large meshes in the mouth of the trawl will only herd shoaling species into the trawl.

How does a pelagic trawl change the position of the net?

By altering the vessel speed and / or changing the length of trawl warp between the vessel and the trawl doors, the position of the net in the water column can be altered to suit the depth where the shoal of fish are swimming at.

Can a demersal fish escape a pelagic trawl?

Occasionally some of the larger demersal species may encounter a pelagic trawl when they move up in the water column feeding on small pelagic fish. Any demersal fish that may stray into the path of a pelagic trawl will usually easily escape through the large meshes in the forward part of the trawl.

Can a cetacean enter a pelagic trawl?

Very occasionally there may be a by catch of some cetaceans that enter the trawl chasing the shoals of pelagic feed fish. In some fisheries where there was evidence of cetacean by catch this fishing method has been banned. This is usually confined to pelagic pair trawls rather than the single trawls.