The birds were shot at Norton Mills lake in North Stainley, which could have put people's lives at risk as well.
Police say the eight geese and swans were shot and left to die.
More top news
A look ahead at the forecast for the Tyne Tees region.
Gale force winds and spells of rain to start the weekend. The Met Office have now issued a warning
Paul Brand meets more parliamentary candidates in our last political programme before the General Election. Watch it here: