2021 North-East England shellfish die-off

The 2021 North-East England shellfish die-off was a series of occasions where a mass of shellfish were found on beaches on the Durham and Yorkshire Coasts in northern England, either dead, or in stages of dying. These events first occurred in October 2021, with re-occurrences in February, and September 2022, with concerns being raised at the amount of crabs, lobsters and other marine animals found dead. An initial investigation by the Department for Environment, Food and Rural Affairs (Defra) stated a large algal bloom had killed off the marine life. However, those working in the fishing industry and independent scientists, claimed the deaths was caused by pyridine poisoning, an effect of dredging in the River Tees. A second government investigation, published in January 2023, stated neither an algal bloom or pyridine poisoning could explain the deaths over such a long period of time, wide area and the unusual twitching in crabs. The scientists concluded that a disease, "novel pathogen" was the "most likely cause of the mortality."