Bird enthusiasts are in a flutter after a rare sighting of Australia's largest owl, the powerful owl, spotted devouring ringtail possums and sulphur-crested cockatoos in a suburban Canberra park.

The owl has taken up long-term residence in Haig Park near the CBD, and bird watchers from across the country and even overseas have flocked to catch a glimpse of it.

The sighting of the owl follows reports in recent days of another type of owl terrorising a small town in the Netherlands.

Residents of that town have been advised to arm themselves with umbrellas at night.

However, an owl expert said while the powerful owl did hunt at night, there was little chance it would sink its talons into Canberrans or their pets.

"It is classified as an apex predator, so what they will do is hunt a variety of food, mainly tree-dwelling mammals," National Zoo and Aquarium senior keeper Brendan Sheean said.

Brendan Sheean said powerful owls were classified as apex predators and mainly hunted tree-dwelling mammals. ( ABC News: Adrienne Francis )

Canberra Ornithologists Group (COG) member Terry Bell said the big predator had been caught on camera devouring sugar gliders and feathery cousins, like Canberra's emblem bird the gang-gang cockatoo.

"These feathers in front of me which are sections of wings showing grey with pinkish feathers... I would think that they are actually from galahs," he said.

Mr Bell was among the first to spot owl scats on the tarmac outside the Turner Bowling Club in north Canberra and then locate the powerful owl in large oak trees in the adjoining Haig Park.

He said powerful owl populations were in decline in Sydney and across New South Wales and the birds were classified as vulnerable.

That meant bird enthusiasts from far and wide had been staking out the park for months, armed with tripods and binoculars.

"Keen bird watchers can really travel vast distances to come and see a bird they hadn't seen before. That becomes a sort of 'lifer' for them," he said.

Turner Bowling Club manager Jeremy Wilcox said the club was even looking to capitalise on the owl's ongoing popularity with visitors and patrons.

"We thought about a powerful owl burger, but that doesn't quite work, so we are going to go with the powerful owl cocktail, which enables you to see all night apparently," he said.

"It is quite a coincidence actually that the Owls Rugby Club plays down the road and bases itself at this club.

"We think it is quite a good omen for their season coming up. They are going to end up in the semi-finals for sure."

DNA test needed to confirm gender of owl

Mr Sheean said the owl may also have moved to the park looking for a mate.

He said once partnered, powerful owls could breed for 30 years, and the season of owl love was fast approaching.

Sorry, this video has expired Australia's largest owl sets up home in Canberra park ( Adrienne Francis )

"There's plenty of food and it could have been a young one that might have turned up looking for a new territory," he said.

He said a DNA test was required to confirm whether the owl was a he or she, and keen bird watchers had already sent feather samples in for testing.

"A lot of people love owls," he said.

"They are such a beautiful animal that is normally involved in a lot of mythical legend, and to see one during the daytime is very uncommon."

Many Canberrans would be more familiar with a controversial rendering of the powerful owl by Melbourne sculptor Bruce Armstrong.

His $400,000 eight metre fibreglass sculpture was purchased as part of the ACT's public art program and it sits beside Belconnen Way.