The resident ecologist at Norton Mills lake has said that people's lives were put at risk by the person or people who shot to death the geese and swans.
Brian Morland said that police believed a large calibre rifle was used to shoot the birds through the wings and legs.
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Every season, we head towards the end of October in the same position - we're learning to fly while we're already in the air.
The group say A&E departments in County Durham, Teesside and North Yorkshire are under threat.
Examples include the switching of ‘bairn’ for ‘baby’, along with ‘kets’ for sweets and ‘netty’ for toilet