Swans out with their cygnets in Perth

To ensure Perth's cute cygnets grow up to be beautiful swans, motorists are being warned to take care on busy roads and highways where the bevy of birds are crossing.

Department of Parks and Wildlife officer Cameron Craigie said it was important people did not disturb nesting swans or try to get close to them because males were particularly aggressive when protecting their cygnets.

"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.