Midwater Trawl

A Commercial Fishing Practices

Midwater Trawl

The midwater trawl is used in both the neritic and oceanic zone and in midwater.
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How it Works

The trawl is about 20 feet long and travels from 200 meters all the way to the bottom of the ocean but not along the bottom of the ocean. The trawl has hoops located along the net with the largest at the mouth, or opening, and the smallest at the end of the net, which keeps the shape of the net in tact. The net is towed by the boat at speeds up to five knots. These trawls are ideal for catching shrimp, fish, squid, and exploring unexplored areas in the midwater zone for new organisms.

Types of organisms caught by the Midwater Trawl

Midwater Trawling catches pelagic fish that means that the type of fish are anchovies, shrimp, tuna, squid, mackerel

How midwater Trawling harms the ecosystem

This can harm non-target species like the sea turtle and disrupt fish activities by using the engine noise, but is known as the "cleaner" way of fishing because it does not have any equipment that creates damage on the bottom of the ocean floor. There is also a great amount of by-catch that can be detrimental to other organisms like whales.

Ways of mitigating the effects of midwater trawl

The Turtle Excluder Devices reduce mortality rate of whales and turtles by helping the organisms escape through the device if entangled in the net.

If the government banned midwater trawling...

If the government banned this type of fishing thousands of fisherman would lose their jobs, the seafood market would crash and seafood restaurants would go out of business. Mid water trawling is vital for jobs and the seafood industry.

Bycatch

Mid water trawling is relatively safe for animals when compared to deep water trawling. In a survey of 377 days at sea 18 dolphins and 4 seals were captured. Based on the hundreds of thousands of tons of fish that trawling brought in ( Over 110000 tons of Horse Mackerel alone) the bycatch cost is relatively minimal.

government control of midwater trawling

Massachusetts requires a permit for trawling with a flat fee. In Australia fishermen are limited by a quota system that restricts the amount of days that the boat may be out at sea based on the quota.

Is it environmentally sustainable?

Although there is a small amount of bycatch in midwater trawling, it is quite sustainable ecologically. There is no damage to the ocean floor and the nets have little impact on surrounding ecosystems. Most midwater trawling is conducted in places with a heavy population of organisms making their impact limited.