Rowers in Cambridge have called for the Queen to remove an aggressive swan nicknamed "Mr Asbo" which they claim attacks people using the river.
The bird patrols a 1,600ft (488m) stretch of water near its nest in Fen Ditton, a spokesman from the Cambridgeshire Rowing Association said.
President Bill Key said the swan flaps its wings and pecks rowers and boats.
Mr Key said the cox of his crew is afraid to go into the water because she was injured in an attack by the swan.
The Cam Conservators said they have been in discussions about its removal.
Her Majesty's Warden of the Swans, Prof Chris Perrins, who works in the zoology department at Oxford University, said: "The Crown does not own this bird but it can claim it."
He said it is essential that permission is sought from Her Majesty's Swan Marker, David Barber, who advises on behalf of the Crown whether a claim for ownership will be made.
If approval is given, a licence must be collected from Natural England.
Prof Perrins said the options include relocating the swan or clipping the feathers on one wing to discourage aggressive behaviour by throwing it off balance when it attacks.
Mr Key said that 1,000 local rowers and 2,000 university students use the stretch of water.
"This swan caused untold disruption and injury last year and the same thing is happening again now," said Mr Key.
"There have been dozens and dozens of attacks.
"The cox of my own crew is frightened to go in the water because she received bruising from an attack in the past."