A hunt will soon get under way in Christchurch's red zone for a pair of invasive myna birds.
Myna birds are considered a pest, and although common in the upper North Island, they are not normally found in Canterbury.
The Canterbury Regional Council said mynas are territorial and aggressive toward other birds, and have been known to remove native species from their nests for their own use.
It said the birds can cause considerable economic loss when they gather in large numbers to feed on stock food, crops or fruit.
The council has now commissioned a contractor experienced in bird control to visit the area where the common myna birds have been reported.
Council principal biosecurity advisor Laurence Smith said the contractor would first visit the area to assess the situation, and then was likely to make a plan to return and shoot one or both of the birds.
He said the contractor was a specialist in removing pests from an urban area, and would get police permission to use an air rifle in the area.
A lone myna bird has been spotted regularly in the Christchurch suburb of New Brighton since around 2018, but in the last month there were reports, and then photographic evidence, of two birds.
John Stewart, a keen amateur photographer, has kept an eye on the first bird over the years after his wife spotted it back in 2018. He said they have often seen the bird near earthquake-damaged red zone land by Pages Road in New Brighton.
Recently, Stewart heard talk of a second bird in the same spot, and he managed to catch a photo of the pair.
"For the last six years we've seen the one, sometimes a couple of times a week, and then you don't see it for a couple of months and then you see it again, but there's never ever been two."
Stewart said he understood the decision to remove the birds.
"We're going to miss our myna, but they don't live forever anyway."
Birds New Zealand Canterbury regional representative Anita Spencer said if the birds remained and bred, they were likely to have a negative impact on native birds, as they are known to be aggressive and territorial and to kick other birds' eggs out of their nests.
However, she said mynas were nowhere near the top of the list of threats to native birds.
"Our native birds do have a lot of threats - cats, stoats, rats - and we don't need to add another one. And myna are very visible, like magpies. People don't often see rats or stoats attacking nests, so it is easier to see the threat they are".
University of Auckland School of Biological Sciences lecturer Anna Santure said myna birds were originally from southeast and southern Asia. The myna birds now in New Zealand originated from India.
She said in the 1860s, acclimatisation societies in Melbourne introduced them to Australia, and about a decade later similar societies in New Zealand brought them to Dunedin and Christchurch. Acclimatisation societies were groups who wanted to bring non-native species to their environment.
"The acclimatisation societies at the time - which were mostly rural societies - were really worried about grain pests, about insects eating grain. They thought myna would be a good bio-control for that. But it turned out [myna birds] preferred the grain to the pests."
She said the birds did not last in the South Island, with the winter temperatures seeming to be a major constraint on successful breeding, but the birds moved north and were now well established in the upper North Island.
Santure said the birds were often unpopular visitors. with people put off by their harsh squawk and aggressive nature, but she could see some of their charm.
"They are sort of bolshy characters. I enjoy watching them kind of strutting their way around. They sort of have their superhero mask on and walk around like they own the place, but they are definitely not at home here in New Zealand."