The increase is causing the birds to become a nuisance and a threat to the ecosystem, The Independent reported.

Since 1990, the population of the graceful, elegant birds has increased by a quarter. Their numbers are reportedly threatening fish, birds and other animals that rely on vegetation to survive, but the swans continue to be under heavy protection by the queen.

"There are more and more swans and they are really threatening biodiversity," said one ministerial source. "We can't do anything because they are heavily protected."

The burgeoning populations are not helped by the increasingly mild winters Britain has been experiencing over the past decade, The Independent reported.