Petition Number: P-06-1547 Petition title: Sea bottom trawling is killing our marine wildlife… Stop bulldozing our marine wildlife! Text of petition: Sir David Attenborough's latest documentary, Oceans, highlights the fact that a shocking 97% of our marine protected areas (MPA), created to safeguard ocean habitats, are being destroyed by being dredged and bottom trawled. We call on the Welsh Government to ban all forms of bottom trawling by both foreign and UK vessels in Welsh waters. We are in an ecological emergency and need action now. If we do not take action now, we will have no chance of stopping the shocking loss of biodiversity or mitigate the impacts of climate change. This widespread fishing practice involves dragging heavy metal nets along the seabed, effectively bulldozing all sea life before it! New research has revealed that this system of fishing pumps out one gigaton of carbon every year. This carbon is released from the seabed sediment into the water, and can increase ocean acidification, as well as adversely affecting productivity and biodiversity. Marine sediments are the largest pool of carbon storage in the world. In fact fishing boats that trawl the ocean floor release as much carbon dioxide as the entire aviation industry! There can be no place for bottom trawling in a modern nature friendly Wales!   The text provided above is submitted by the petitioner. The petitions team make every effort to ensure it preserves their authentic voice. This text has not been verified for accuracy, or errors, and may contain unverified opinions or assertions.

 

 

1.        Background

Bottom trawling is a method of fishing in which weighted nets are dragged across the seafloor the capture species living on or near the seafloor. This type of fishing includes:

§    Beam trawlers which target fish on the seabed by towing a net from either side of the boat.

§    Demersal trawlers which fish along or just above the seafloor to catch demersal (bottom-dwelling) fish. A funnel-shaped net is towed behind one or two boats.

§    Dredges, which are rigid structures towed along the seabed by a boat. They are used to target shellfish species such as scallops and oysters.

The Wildlife Trusts say that bottom trawling results in the indiscriminate capture of wildlife, the discarding of a large proportion of caught animals, and the release of carbon from the seafloor to the atmosphere. A 2020 report by Natural Resources Wales (NRW) found that the top 10cm of Welsh marine sediments store at least 113 million tonnes of carbon – equivalent to almost 170% of the carbon stored in Welsh forests.

The Marine Stewardship Council says the impact of bottom trawling on ecosystems is dependent on habitat sensitivity and the design of trawling equipment. A 2021 study by the Marine Conservation Society looked at the impact of a bottom trawling ban in three UK Marine Protected Areas (MPAs). It found that biodiversity increased by an average of 21% within five years of the ban coming into force.

 MPAs are sites with a level of protection for nature in the sea. Wales has 139 MPAs (comprising five different designations), collectively covering around 50% of its waters. Not all ecosystem features are protected in MPAs. For example, Wales’ largest MPA is the West Wales Marine Special Area of Conservation, whose sole protected feature is the harbour porpoise. Skomer Marine Conservation Zone (total area 13 km²) is the only Welsh MPA where bottom trawling is entirely banned. A 2019 Senedd Research briefing provides more background information on the Welsh MPA network.

Map of Welsh Marine Protected Areas

Source: Welsh Government

The Welsh Government has broad competence over the management of inshore waters (also known as ‘territorial seas’), which extend up to 12 nautical miles from the coastline. The Senedd gained legislative competence over fisheries in the whole Welsh zone under the Fisheries Act 2020, although access arrangements for EU vessels post-Brexit are set out in the UK-EU Trade and Cooperation Agreement (TCA). The TCA’s fisheries conditions were recently extended to 2038 under the UK-EU Common Understanding. Fisheries Management Plans (FMPs), developed by the UK and devolved governments, are the primary policy mechanism for the sustainable management of fisheries.

The UK Government’s Marine Management Organisation is currently consulting on proposed bottom trawling bans within around 30,000 km² (approximately one third) of England’s MPA network.

2.     Welsh Government action

In his response to the petition, the Deputy First Minister and Cabinet Secretary for Climate Change and Rural Affairs, Huw Irranca-Davies MS, says there is limited use of trawls among the largely small-scale and inshore Welsh fishing fleet. He says the main trawl deployment by Welsh vessels occurs in the king scallop fishery, which is regulated through the joint Welsh and UK government King Scallop FMP. The Welsh Government has also commissioned Bangor University “to investigate seabed sensitivity and benthic ecosystem integrity in areas of scallop fishing to inform future management”.

The Cabinet Secretary says future limitations on bottom-towed gears would be implemented as part of future FMPs, including the planned Irish Sea Demersal FMP and Celtic Sea and Western Channel Demersal FMP. Both FMPs are due for publication in 2026.

He also highlight NRW’s recent reports assessing the condition of Welsh MPAs. The reports looked at 84 designated features within inshore MPAs and found that “no assessed habitat or species within the MPA network were found to be in an unfavourable condition due to impacts caused by fishing”.

3.     Welsh Parliament action

A short Senedd debate on 9 July 2025 considered the question ‘Should the Welsh Government prohibit bottom trawling in Wales?’.

The Climate Change, Environment, and Infrastructure Committee undertook an inquiry on Marine environment management in 2022. Recommendation 17 of its reportsaid “The Welsh Government should set out the purpose and timeline for the public consultation on dredging and bottom trawling in Welsh MPAs”. The Welsh Government accepted the recommendation, saying that proposals for any management measures will be consulted on after the conclusion of towed gear assessments in summer 2022. Although specific Welsh Government consultations since 2022 have mentioned dredging and trawling (such as consultation on the King Scallop FMP), no broader consultation on restricting towed gear within MPAs appears to have taken place.

In 2021, the Petitions Committee considered a petition with 205 signatures entitled “Sea bottom-trawling is killing our marine wildlife … Stop bulldozing our seas!”. Further background information can be found in the briefing for that petition.

Every effort is made to ensure that the information contained in this briefing is correct at the time of publication. Readers should be aware that these briefings are not necessarily updated or otherwise amended to reflect subsequent changes.