Toxic Algae Kills Swan Family at Canvey Lake
Get the Energy newsletter
Daily energy & climate — solar, EVs, oil, the policy fights and tech bets shaping the transition. Free.
- Canvey Lake's swan family — two resident parents and nine cygnets this year — all died after the lake tested at 2.5 million cells of blue-green algae per millilitre in July 2025, more than 100 times the 20,000-cell warning threshold.
- Sue Schwar, founder of South Essex Wildlife Hospital, said she was "100% sure" the deaths were caused by blue-green algae exposure; two cygnets were earlier killed by foxes and one of four others taken to the hospital in June died from avian botulism.
- Canvey Island Town Council surrendered its lease of the lake to Castle Point Borough Council after the toxic findings, having allocated £500,000 toward restoration in June.
- Castle Point Borough Council said it was "very saddened" by the loss and confirmed £1m of funding is backing major restoration works at the lake.
- Hayley Cockayne, a Canvey resident who spent four to five hours daily with the swans for three years, said she was "absolutely broken" and called the lake "dead."
- The lake, officially registered as a Local Nature Reserve in 1998, has been hit by similar algal blooms reported across the region during recent heatwave and drought conditions, per the borough council.
Why it matters: The deaths forced Canvey Island Town Council to surrender its 1998 Local Nature Reserve lease to Castle Point Borough Council, transferring responsibility — and a £1m restoration commitment — for a lake where algae levels sat at 2.5 million cells per millilitre, 125 times the warning threshold, leaving a designated wildlife refuge under new management after a complete wildlife loss.
