More species recorded in Mersey than ever before amid concerns over pollution

More species were found in the River Mersey last year than ever before in what is being described as “the greatest river recovery in Europe.”

There were 45 different kinds of fish found in the river in 2023 by The Mersey Estuary Species Hunt, a partnership between anglers and the Mersey Rivers Trust.

This is higher than the 37 species found in the hunt’s first year in 2022 where five types of sharks were found.

The news has been hailed as a sign the river is improving but concerns continue to be raised about continued pollution including from sewage discharges.

Cod, rays, scorpion fish, different types of eel, herring, stickleback, as well as edible species like bass, sole, and plaice were all identified in the river this year. A rare venomous fish called a bluemouth rockfish was also caught off the Wirral coast but not included in the Mersey competition.

Mike Duddy, from the Mersey Rivers Trust, holding a freshly caught cod. Credit; Edward Barnes

Mike Duddy, who came up with the hunt to help monitor species in the river, said, “What it means is the River Mersey is recovering after 200 years of industrial pollution, possibly the greatest river recovery in Europe,” adding, “People travel all over the country and try and catch these fish and all those wonderful fish are now on our doorstep.

“It’s no longer the dirty Mersey. There’s dolphins, harbour porpoises, there’s jellyfish in the docks. All of those things you expect to see on holiday are now here on people’s doorstep in Merseyside and the fact that now people really value them and people in Merseyside really value their wildlife.”

However, he said anglers were finding plastic bags and wet wipes “coming down the river in ever increasing numbers” and urged water company United Utilities to act faster to stop discharging sewage.

Damian Owens with a species of smooth hound shark he caught in the Mersey. Credit: Damian Owens

Damian Owens, who has fished in the river for 37 years, said the river improved around 2000 but believes things could now be going backwards. This year, he caught 41 different species, the most of any angler doing the competition.

He said he’s found dabs – a flatfish that spends all year in the river – with green patches, growths, and parts eaten away by suspected bacteria and whiting – a fish that lives in the river September to February – with sores. He puts this down to polluted water in the river.

He said, “It’s all down to the government and the water companies to change what they are doing. They have got to. It’s not just the Liverpool part of the river. It starts all the way up the river.

“It’s not a quick fix, that is the problem. They have got to change the whole sewage system and the last few years we have had so much rain and storms so they have just dumped it in the river.

“As for all the species, I am not so sure that they are all new, just no one has been fishing for them. They might have always been there but no one ever bothered fishing for them.”

Kiera Tuck with a wet wipe instead of a fish. Anglers said they were regularly catching wet wipes instead of fish. Credit: Edward Barnes

He said plastic waste is also being regularly found too, including those left by humans on the beach not bothering to put it in a bin, adding, “We are finding everything, plastic bottles, wipes, plastic bags. Whenever I go fishing, I have a carrier bag with me and sometimes I fill it but it’s mainly plastic bags and loads of wet wipes.

“You do not see them floating, they are on the floor but then you think you have caught something and it’s a load of wet wipes. It’s pretty common.”

The numbers of different species has also changed this year with far fewer cod and far more sharks caught, a change that he said was linked to warmer sea temperatures and overfishing in the Irish sea.

He said, “Since the cod disappeared, that made a massive difference because cod are quite high up the food chain. They sort of eat everything as they do tend to grow fast but it’s likely disappeared from Wirral because everyone wants cod in their fish and chips.”

A United Utilities spokesperson said, “We’re proud of the role we have played in improving the health of the River Mersey. Since 1985, as a key partner in the Mersey Basin Campaign we have invested more than £3bn in our treatment works and sewer systems to help improve the water quality. It’s great to see that so many species are returning after these improvements have been made.

“We’re not resting on our laurels though. We know there is more to be done. Between now and 2030, we’re planning to invest nearly £2bn in the Mersey and its tributaries to improve our wastewater treatment works and reduce the times that storm overflows operate.”

Local government organisations have also been putting pressure on the United Utilities to take action.

The anglers discovered the Mersey now has at least 45 species of fish. Credit: Edward Barnes

Wirral Council was asked to lobby on the issue following a petition and the local authority’s environment chair Liz Grey said, “I’m confident the next government will take water pollution much more seriously and we can see even greater diversity of species flourishing and an end to wet wipes and worse in our rivers and seas.”

The Liverpool City Region Combined Authority, which has committed to making the river discharge-free by 2030, said, “The Mersey has undergone a remarkable regeneration in recent years. Having once been considered biologically dead, it is a sign of its ongoing recovery that it is now home to such a wide variety of species.

“Yet, despite the progress that has been made, it is clear that there is still a significant amount of work to do.”

The Environment Agency, which monitors the river, said they continued to be “a strong regulator of water companies pointing to increased investment by United Utilities as a result. Three sonar surveys have been carried out on the rivers Mersey, Weaver, and Dee which found healthy numbers of fish and will for the first time analyse fish DNA levels to better understand what’s in there.”

A spokesperson said, “We are delighted by the number of species found in the River Mersey and are working hard as a regulator and with partner organisations to support the on-going recovery and future monitoring of threatened species such as salmon and eel.

“Our work includes ensuring that industrial infrastructure is modernised to protect the internationally endangered European eel and supporting local projects to improve the habitats that this species depends on.”

Lead image: Tony Shep with a cod he caught, a type of fish that had been caught far less in 2023. Credit: Tony Shep

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Damian Owens with a species of thornback ray he caught in the Mersey. Credit: Damian Owens
Karl Nicholls with a bass he caught in the river. Credit: Karl Nicholls