Biosecurity officials are appealing to the public to help them track down a large number of angry birds on the loose in Auckland.
The Ministry for Primary Industries (MPI) has confirmed red-vented bulbul have been spotted in Mangere, Devonport and possibly on the Whangaparaoa Peninsula.
It's uncertain how many of the birds are out there.
MPI Response Manager Jaap Knegtmans said red-vented bulbul are aggressive pests that have developed a reputation as one of the world's most invasive birds.
There are concerns the bird will damage Auckland's horticultural industry, native vegetation, birdlife and private gardens.
He said MPI had teamed up with the Department of Conservation and Auckland Council to track down the birds and eradicate them.
While the birds may appear cute, they're anything but, Knegtmans said.
"We'd like to hear from members of the public who believe they've seen these birds and the sooner we can hear about a potential sighting, the better."
Red-vented bulbuls have invaded other parts of the Pacific, including Fiji and suburban Sydney, and may have hitched a ride to New Zealand on a commercial vessel or recreational yacht, Knegtmans said.
They have been found in Auckland before - in the 1950s and more recently in 2006. In both instances they were eradicated.
Red-vented bulbuls are a medium-sized bird around 20cm in length from body to tail.
They are generally dark coloured with a lighter chest and rump, a small crest on their head, and significantly, a very distinctive crimson-red patch beneath their tail.
The red patch was the bird's key identification feature, Knegtmans said.
If you see a red-vented bulbul, contact MPI on its free Exotic Pest and Disease Hotline - 0800 80 99 66.