Jan 27, 2023
Normally, a shark sighting in a river would be cause for alarm. For the scientists who’ve spent years cleaning up the River Mersey in England, though, it's a welcome sight. It's proof that their hard work has paid off. Eels, sea scorpions, and smelt are back too.
The Mersey runs through Manchester and Liverpool. Those areas have a lot of factories. During the 19th and 20th centuries, companies threw chemicals and sewage into the river. Locals used to joke that a person couldn’t drown in the Mersey. They said “you’d die of poisoning first.” Dr. Peter Jones of the Mersey Basin Campaign told The Independent that the Mersey “was as bad as you could get.”
Scientists surveyed fish species in the river in 2002. Only 15 were found throughout the Mersey, even in its cleanest sections. They redid the survey in 2022. It found that that number had more than doubled to 37. Mike Duddy of the Mersey River Trust said the rebound was due to regional initiatives.
"Since (1985) there's been billions of pounds spent on wastewater treatment works in the region. That's prompted this … recovery,” Duddy told the BBC. “Everyone says that our wildlife is in decline, (but) that's actually the opposite in the Mersey where wildlife is on this rapid improvement curve."
While Duddy cheered the efforts of local groups, he stressed that the Mersey is “only partway there.” Recent cleanups have yielded hundreds of pounds of rubbish, including masks and wet wipes. Still, the Mersey is “the best environmental good news story in Europe without a doubt,” Duddy said.
Photo by OpenStreetMap contributors courtesy of Wikimedia Commons.
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