Warnings as magpie swooping season takes flight

Magpie swooping season has started early, and cyclists are in the firing line.

The birds, who are now in breeding mode, have been spotted striking cyclists more than 10 times in one hit.

Melbourne cyclist Matthew Stacy said he can encounter three or four birds on his morning ride, and they're certainly not afraid to get close.

"They can hit the helmet pretty hard, it gives the head a bit of a knock," Mr Stacy told 9NEWS.

"Without the helmet they would draw blood, they draw blood on the cheeks sometimes," he said.

Given he rides with a GoPro camera, he's been able to capture some sensational - yet slightly scary - pictures.

"I hold the GoPro out in front of me, I get the footage of them coming at me from behind, " he said.

Experts from the Department of Environment, Land, Water and Planning say the official swooping season has started early because of warmer than average weather.

"They've started to breed and they're swooping to protect eggs and chicks in the nest," Suriya Vij said.

Ms Vij said only five percent of magpies that actually do the swooping - and that the majority are male.

"It's not every magpie by any means, but it is behaviour that's in response to a perceived threat," she said.

Hotspots include anywhere in open spaces, near nesting treas and areas along the Yarra and Maribrynong Rivers in Melbourne.

Authorities said some ways to avoid being swooped include walking in groups, carrying an umbrella or stick, and wearing a hat.

Sightings can be also reported on the wildlife department's online magpie map.