Bottom trawling has a disastrous climate impact by disturbing carbon sequestered on the sea floor, which is turned into CO₂ and then makes its way into the atmosphere with a footprint equivalent to the entire aviation industry. This common commercial fishing practice, where huge, weighted nets are dragged across long distances on the sea floor, also negatively and severely impacts marine ecosystems and biodiversity. The nets catch anything in their path, including turtles, invertebrates and other non-target species, and tear up long-lived and slow-growing deep-sea coral forests. 

Background and context

Bottom trawling is a method of commercial fishing in which boats drag huge, weighted nets across the sea floor. These nets, usually cone-shaped to trap fish and prawns that live on the sea floor, are held open by metal or wood beams, and have heavy wheels that help them move long distances across the sea floor. The impact of bottom trawling on marine ecosystems and biodiversity is well established. The nets catch anything in their path, resulting in huge quantities of bycatch including turtles, invertebrates and other non-target species; long-lived and slow-growing deep-sea coral forests are torn up, and seabed sediment is disturbed. 

New research has found this fishing practice also has a disastrous climate impact. By disturbing the sea bed, bottom trawling also disturbs carbon that has been sequestered away into the sediment, where it could be safely stored for millennia. Part of the disturbed sediment carbon turns into carbon dioxide underwater, and up to 60% of it makes its way into the atmosphere within nine years, where it contributes to global warming. An estimated 370 million tonnes of carbon are released into the atmosphere each year by bottom trawling - a similar footprint to the entire aviation industry. The remaining 40% of carbon from disturbed sediment remains in the ocean, where it can contribute to localised ocean acidification that further strains marine biodiversity and ecosystems.

Australia’s most intensive bottom trawling takes place in southern Queensland, including the southern Great Barrier Reef. Bottom trawling is also practised in northern New South Wales, where prawn fishing is common, and in the South East Trawl Fishery, which covers a huge area from Barrenjoey Point north of Sydney, around Tasmania to Cape Jervis in South Australia, where it is used to catch bottom-dwelling fish. The industry has benefited from repeated government bailouts as it struggles to cope with decades of overfishing and global warming decimating fish stocks. If Australia is serious about protecting its marine ecosystems and fighting climate change, it’s time for urgent and decisive government reforms of bottom trawling policies.

These concerns, and others plaguing our oceans, are expected to feature at the upcoming UN Ocean Conference in France this June, where the Nice Ocean Action Declaration - the final outcome of the conference, prepared under the responsibility of the Ambassadors and Permanent Representatives to the UN of Australia and Cape Verde, the two co-facilitators appointed by the UN General Assembly in July 2024. The Declaration will call for accelerated action to address destructive practices like bottom trawling as part of the broader effort to meet SDG 14 'Life below water' and address urgent threats facing our ocean.  

Why is this important?

• Bottom trawling causes irreparable harm to Australia’s marine ecosystem
• Bottom trawling also has disastrous climate impacts, including the release of carbon dioxide from the sea floor and reducing the ocean’s capacity to sequester atmospheric carbon

Desired outcomes: 

• A ban on bottom trawling to protect biodiversity and reduce carbon emissions from disturbed sediments, coupled with a transition plan for the fishing industry that supports sustainable alternatives

Who to contact

• Your local Federal MPs (check on this website if you’re unsure who that is)
• Key Federal Labor (addresses in link) including Resources Minister Madeleine King, Prime Minister Anthony Albanese; Treasurer Jim Chalmers; Climate and Energy Minister Chris Bowen; Environment and Water Minister Murray Watt; Trade and Tourism Minister Don Farrell
• Federal Senate Crossbenchers (addresses in link) including Greens, David Pocock (ACT independent), Jacquie Lambie (JLN) and Tammy Tyrell, who hold the balance of power in the Senate

Resources:

• Watch David Attenborough's film, Ocean
• Email example below and General email template here to write your own from scratch
• Guidelines and tips for writing emails

Actions you can take:

1. Email your MP or relevant Ministers

If you need some help getting started with your email, here is an example. 

Please don’t copy it exactly - personalise it and tailor it to the MP you are writing to. 

In addition, when writing to a Minister or Shadow Minister, start by saying that you’re writing to them in their role as Minister for xxxx, otherwise they will probably just forward your email to your local MP.

[MP name]

[Member for …. or  Minister for ….]

Dear …

[Include a personal statement - who you are and why you care]

Bottom trawling is a method of commercial fishing in which boats drag huge, weighted nets across the sea floor. The impact of bottom trawling on marine ecosystems and biodiversity is well established: the nets catch anything in their path, resulting in huge quantities of bycatch including turtles, invertebrates and other non-target species; long-lived and slow-growing deep-sea coral forests are torn up; and seabed sediment is disturbed.  

But did you know this practice also adds significant amounts of carbon into the atmosphere, contributing to global warming?

By disturbing the sea bed, bottom trawling disturbs carbon that has been sequestered away into the sediment. It could have been stored here safely for millennia, but instead it turns into carbon dioxide and, over a period of about nine years, 60% of it makes its way into the atmosphere. This contributes 370 million tonnes of carbon into the atmosphere each year - the equivalent of the entire global aviation industry. Carbon that doesn’t make it to the atmosphere remains in the ocean, where it can contribute to local ocean acidification and puts our marine ecosystems under further stress. 

The ocean is a way of life in Australia, and being able to continue to enjoy it through surfing, boating, recreational fishing, swimming and diving is one of the best things about our country. If we are serious about protecting these marine ecosystems and fighting climate change, it’s time for urgent and decisive government reforms of bottom trawling policies.

Will you call for a ban on bottom trawling to protect biodiversity and reduce carbon emissions from disturbed sediments? 

I look forward to your response.

Sincerely

Name

Address

Phone

(required if you want a reply)

Hi, my name is ….. and I’m a voter in [your electorate].

I’d like to speak to …..[name of MP]

(Staffer will probably say: I’m sorry they’re not available, can I take a message?)

Yes, thank you! Would you please tell them that:

• I’m concerned about the impacts that bottom trawling has on our oceans. It’s terrible for marine biodiversity, and also contributes as much carbon dioxide into the atmosphere each year as the entire global aviation industry
• It’s time to put an end to destructive fishing practices like bottom trawling. As well as having disastrous impacts on marine life, it contributes to global warming and ocean acidification by disturbing carbon held in the sea bed. 
• I’d like to see a complete ban on bottom trawling, and our fishery industries supported with a plan to transition to more sustainable practices 

And ask them to:

• Call for a ban on bottom trawling to protect biodiversity and reduce carbon emissions from disturbed sediments.

Thank you!

Extreme weather and climate change