Trawling is changing seafloor habitats: study

Sep 05, 2012
A trawling boat passes the shore in Hong Kong in 2011. Bottom trawling is dramatically altering the ocean floor and harming habitats, similar to the way that farming has permanently changed the landscape, a study said on Wednesday.

Bottom trawling is dramatically altering the ocean floor and harming habitats, similar to the way that farming has permanently changed the landscape, a study said on Wednesday.

Much has been written about trawling's indiscriminate destruction of fish stocks, but a team of in Spain, writing in the journal Nature, said some of its practices damaged the fabric of the ecosystem.

Continental slopes, the gradients that connect the shoreline with the ocean floor, are being smoothed out in areas that are intensively bottom-trawled, the team said.

entails dragging heavy nets and gear along the ocean floor to haul up fish species that feed near the sea bed.

But it leads to vast displacement of sediment and changes to the submarine landscape, the team said.

This disturbs complex ocean floor habitats, "potentially affecting " in a manner comparable with , it said.

In the northwestern Mediterranean, where industrialised trawling has been taking place since the mid-1960s, the scientists found the practice displaced 5,400 tonnes of sediment in just 136 days they monitored.

"Trawled continental-slope environments are the underwater equivalent of a gullied hill slope of land, part of which has been transformed into crop fields that are ploughed regularly, thus replacing the natural contour-normal drainage pattern by levelled areas," they wrote.

And while farmers ploughed a few times per year, sea trawling can occur almost daily.

The paper argued that trawling be added to the list of Man's damaging ocean legacies along with such phenomena as sea-level rise and acidification.

Conservationists say a trawling ban will not just conserve but give soft corals, sponges and other bottom-dwelling creatures a chance to recover.

Explore further: Japan to hunt fewer whales in Pacific this season (Update)

More information: DOI: 10.1038/nature11410

add to favorites email to friend print save as pdf

Related Stories

Hong Kong bans trawling to save fish stocks

May 20, 2011

Hong Kong has banned trawl fishing in its waters, a decision welcomed by conservationists Friday as a crucial move to save fish stocks and revive the city's depleted marine environment.

Gulf of Maine groundfish trawling studied

Feb 07, 2006

University of Maine scientists say they have completed a long-term study of the effects of groundfish trawling on the sea floor of the Gulf of Maine.

Bottom trawling impacts, clearly visible from space

Feb 15, 2008

Bottom trawling, an industrial fishing method that drags large, heavy nets across the seafloor stirs up huge, billowing plumes of sediment on shallow seafloors that can be seen from space.

Cliffhanging corals avoid trawler damage

Jan 20, 2012

Bottom trawling fishing boats have devastated many cold water coral reefs along the margin of the North East Atlantic Ocean. Now, researchers have found large cold water coral colonies clinging to the vertical ...

Recommended for you

Plants with dormant seeds give rise to more species

20 hours ago

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Scientists tether lionfish to Cayman reefs

Apr 18, 2014

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

jerryd
5 / 5 (1) Sep 05, 2012

This form of fishing destroys so much sealife that they alone are responsable for probably 30% of fish decline. Sadly little of this is used, like 5%, wasting 95%. And they wonder why the fish are gone!!

We need to stop destorying the habitat that makes the seafood we want. If done right we could harvest 3x's our current rates forever.
Cave_Man
5 / 5 (1) Sep 05, 2012
Seriously, why do they not try and get the message out! 90% of the fish in the ocean are GONE DEAD GONE!

..as compared to per-industrial fish stock levels.

Sickening. Fish may be good for you and healthy and whatever but we need to stop before it's all over. Permanent damage is relatively easy to incur on our planet than anyone ever realized. But if mankind were smart enough we could have everything we want and not touch a single bit of the wild earth.

I would love to live in a space habitat and grow food. Solar panels and asteroids or moon material is all you would need.

More news stories

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

Plants with dormant seeds give rise to more species

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.

Health care site flagged in Heartbleed review

People with accounts on the enrollment website for President Barack Obama's signature health care law are being told to change their passwords following an administration-wide review of the government's vulnerability to the ...