Department of Parks and Wildlife officer Cameron Craigie said there had been recent reports of swans and cygnets walking across busy roads and highways.
�Swans often don�t nest at a waterway, just in the vicinity of it, and once the family is mobile, they are out and about and in danger of being hit by vehicles,� he said. �The department is asking motorists to take care to avoid swans without endangering themselves or other road users.�
Mr Craigie said it was important not to disturb nesting swans.
Adult and juvenile swans and ducks are also known to cross the Kwinana Freeway in the vicinity of wetlands.
If people see sick or injured wildlife, call 9474 9055.