Dropline
Encyclopedia
A dropline is a commercial fishing device, consisting of a long fishing line
Fishing line
A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material, and weight...

 set vertically down into the water, with a series of fishing hooks attached to snood
Snood
Snood can refer to:* Snood , a type of hood or hairnet worn by women* Snood , a puzzle game* A caruncle or comb that hangs over the beak of a turkey* A type bait holder used on a crabbing trotline...

s.

Droplines may be set either down underwater cliffs or just in the water column. They have a weight at the bottom of the line and a float at the top. They are not usually as long as longlines and have fewer hooks.

Droplines can be contrasted with trotline
Trotline
A trotline is a heavy fishing line with baited hooks attached at intervals by means of branch lines called snoods. A snood is a short length of line which is attached to the main line using a clip or swivel, with the hook at the other end. A trotline can be set so it covers the width of a channel,...

s. Whereas a dropline has a series of hooks suspended vertically in the water, a trotline has a series of hooks suspended horizontally in the water.

Conservation impacts

A concern for marine conservation
Marine conservation
Marine conservation, also known as marine resources conservation, is the protection and preservation of ecosystems in oceans and seas. Marine conservation focuses on limiting human-caused damage to marine ecosystems, and on restoring damaged marine ecosystems...

 is that droplines are able to access areas that are otherwise natural fish refuges, such as deep sea canyons and seamount
Seamount
A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface , and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from a seafloor of depth. They are defined by oceanographers as...

s.

The Australian Marine Conservation Society
Australian Marine Conservation Society
Australian Marine Conservation Society is an Australian independent and not-for-profit organisation, founded in 1965, is dedicated solely to protecting the health and vitality of Australia's coasts and oceans...

 rates dropline fishing as having a "moderate impact" on wildlife and a "low impact" on marine habitats.

Droplines have the potential to interact with orca
Orca
The killer whale , commonly referred to as the orca, and less commonly as the blackfish, is a toothed whale belonging to the oceanic dolphin family. Killer whales are found in all oceans, from the frigid Arctic and Antarctic regions to tropical seas...

s (killer whales). There is predation by orcas on commercial longline and dropline fish catches, including around Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

, Bering Sea
Bering Sea
The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....

 and Prince William Sound
Prince William Sound
Prince William Sound is a sound off the Gulf of Alaska on the south coast of the U.S. state of Alaska. It is located on the east side of the Kenai Peninsula. Its largest port is Valdez, at the southern terminus of the Trans-Alaska Pipeline System...

areas, causing significant financial loss to commercial fishers, and threat to orcas, which can become caught or entangled, exposed to ship strikes when moving or migrating, or suffer retaliation from fishers. Retaliation in response to predation on fish catches in previous decades has included shooting and harpooning of orcas.

External links

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