What is ghost gear and why is it so harmful to marine life?

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Ghost gear is the name given to lost or discarded fishing gear. It is responsible for killing thousands of marine animals every year.

Due to most fishing fear being made from plastic, ghost gear can go on trapping and killing animals for years or decades after it was first abandoned.

What kind of equipment is classed as ‘ghost gear’?

Top left: gillnets, top right: crab pots, bottom left: crab traps, bottom right: trawls

Ghost gear can result from any type of fishing: large-scale industrial fishing, small-scale fishing, and even recreational fishing. Any type of gear lost or abandoned is classified as ghost gear.

The most common type of derelict fishing gear are gillnets, crab pots and traps, longlines and trawls.

What are the consequences of ghost fishing?

Ghost gear does not discriminate: it traps small animals, large animals, and endangered animals

Fishing equipment is usually designed to capture a particular species of animal, and when it is not in use, it will be stowed aboard a boat, or back on land. Ghost gear, however, will remain in the ocean, continuing to catch the target species, as well as other species of marine animal. This is called a ‘ghost catch’.

When an animal becomes trapped in a piece of ghost gear, it will often die as a result of either starvation, predation, or cannibalism.

Because of the durability of plastic, ghost gear can continue to be active for many years after it was lost, trapping and killing hundreds or thousands of animals over its lifetime, including commercially valuable or threatened species.

An estimated 100,000 marine animals are killed by plastic in the ocean every year.

Other negative consequences of ghost gear include:

  • Damage to underwater habitats, including coral relief and benthic fauna
  • Economic loss due to increased marine life mortality

How does fishing gear become ‘ghost gear’?

There are numerous ways in which fishing gear can become abandoned, including:

  • Bad weather could result in the equipment becoming lost
  • The gear could become entangled with other fishing fear, the seabed, or with boats.
  • Older gear could break and cut loose
  • Deliberate disposal – gear no longer required, the boat carrying too much weight, etc.

What is ghost gear made from?

Plastic fishing gear is strong, durable, and does not biodegrade. This is what makes it so effective at catching all manner of marine animals.

Modern commercial fishing gear contains a lot of plastic. It’s not hard to understand why: plastic is durable, cheap, lightweight and does not rust.

Let’s use the example of ‘gillnets’, so named because fish swim through a mesh and usually get entangled by their gills. They are particularly effective, as they are almost invisible in the water, making them hard for fish and other marine life to avoid.

Plastic gillnets are incredibly durable, as plastic does not biodegrade. They will remain intact for a long time.

Some gillnets have been observed to still be ensnaring marine animals 20 years after they were abandoned.

The threat to endangered species

A Hawaiian monk seal (an endangered species) lying on a fishing net

Many of the species of marine animals affected by ghost gear are already endangered, causing a decline in their already meagre population. Examples include:

  • Hawaiian monk seals, a critically endangered species, have been discovered entangled in driftnet. There are only an estimated 1,200 Hawaiian monk seals left in the world, so ghost gear is a real threat to the survival of the species.
  • Two Inso-Pacific humpback dolphins and three Australian snubfin dolphins drowned in nets in Cape Arnhem, Australia, between 2008 and 2011. Both of these species are classed as ‘near threatened’.
  • 29 sea turtles were discovered dead, entangled in ghost fishing nets, over a four-month period. All seven of the species found are either endangered or threatened.

Which parts of the world are affected by ghost gear?

Anywhere fishing gear is used, ghost gear will be found.

Due to ocean currents, ghost gear will often end up in a ‘convergence zone’ – areas of the ocean where large quantities of debris will accumulate.

One such convergence zone is the Great Pacific Garbage Patch. It has been estimated that fishing gear makes up 46% of the patch.

The Great Pacific Garbage Patch is not the only debris convergence zone in the world – other patches exist, including in the South Pacific Ocean and the North Atlantic Ocean.

What types of animals are affected by ghost gear?

All marine life is at threat from ghost gear. Fishing nets, by their very design, are incredibly effective at ensnaring marine animals and not allowing them to escape.

There are numerous videos like the one above of people selflessly risking their safety to free animals from fishing nets, such as this one of a humpback whale, badly entangled by a fishing net.

The heartbreaking sight of a seal with plastic fishing line wrapped around its head

The sad reality, however, is that most animals who become entangled, are not freed by human beings. They are far more likely to starve death, die of exhaustion, or become prey to another marine animal.

As well as whales, some of the animals affected by ghost gear include turtles, seabirds and seals.

To give you a picture of the scale of this problem, a recent study estimates there to be over 85,000 lobster and crab ghost traps in the Florida Keys. Each of these traps is capable of repeatedly catching a variety of marine animals and could remain operational for years.

How can ghost gear be prevented?

From the facts laid out in this article, it should be plain to see that ghost gear is a huge threat to the lives of marine animals.

Governments around the world are more aware of the ghost gear issue than ever before.

Some of the measures being investigated and implemented to try to tackle the problem include:

  • Making improvements to the design of commercial fishing gear to reduce the likelihood of failure
  • More efficient ‘zoning’, to reduce the likelihood of gear becoming entangled with other gear.
  • Working on implementing more biodegradable equipment, so that if gear is abandoned, it is not still active for years or decades.
  • Marking gear with GPS trackers, so it can be recovered more easily.

The Global Ghost Gear Initiative

The Global Ghost Gear Initiative is an alliance of the fishing industry, private sector, corporates, NGOs, academia and governments, dedicated to helping tackle the problem of ghost gear.

They describe themselves on their website as:
Launching in September 2015 and founded on the best available science and technology, the GGGI is the first global collective impact alliance dedicated to tackling the problem of ghost fishing gear at a global scale.

Some of the participants in the initiative include WWF, Nestle, Marks and Spencer, Marine Conservation Society, as well as 13 Governments from around the world.

On their website, they list over 30 ghost gear prevention projects active around the world: https://www.ghostgear.org/projects/?offset=1539226918085

Can ghost gear be removed from the ocean?

The Ocean Cleanup initiative aims to remove 50% of the plastic found in the Great Pacific Garbage Patch over 5 years

‘The Ocean Cleanup’ is an environmental organisation based in the Netherlands whose aim is to remove plastic from the ocean.

The initiative was the brain-child of Boyan Slat, who was just 18 years old when he came up with the idea.

To remove plastic the plastic, The Ocean Cleanup have deployed 600m long floating structures in the sea. The system uses the currents and wind to its advantage, collecting garbage in the center of the floaters.

The Ocean Cleanup system has been deployed in the Great Pacific Garbage Patch, and the team hope to clean up 50% of the plastic in the patch in 5 years.

As discussed previously in the article, ghost gear is estimated to make up 46% of the Great Pacific Garbage Patch. Providing the Ocean Cleanup system works as expected, it should make a significant difference to the amount of harmful ghost gear in the area, and provide a blueprint for future efforts to remove plastic from the world’s oceans.