SWANS at a Wearside park have had to be humanely destroyed after they fell ill with suspected lead poisoning.
The RSPCA has put down three of the birds at Herrington Country Park after they suffered similar symptoms to swans found on other parts of the River Wear which have either died or had to be destroyed due to high levels of lead in their systems.
The latest deaths come after the charity and veterinary practices have dealt with up to 60 fatalities since the start of December.
Many of those have been found in the Wear close to the Riverside Park at Chester-le-Street, with an investigation drawing on the knowledge of the Environment Agency, wildlife experts and police, as well as the animal charity.
RSPCA inspector Jacqui Miller said: “The dead swans are being tested for everything, and are still coming back as having high levels of lead in their systems, though the cause of this is unconfirmed.
“We are getting fewer of them coming to our attention now, but the numbers of swans on the river is visibly affected.
“We have had three in the past week, two dead and one which had to be put to sleep, at Herrington Country Park, with similar symptoms and post-mortems examinations are being carried out.
“We continue to appeal to the public to be vigilant and keep an eye out for these swans if they can.
“If anyone has any specific information that might help our investigation they should call us.”