During winter, dramatic flocks of circling red-billed gulls stopped visitors to Oamaru’s central business district in their tracks as they crossed State Highway 1.
In May, Thames St businesses complained that the hundreds of gulls taking up residence on the roof of Countdown not only produced scenes reminiscent of the Hitchcock classic The Birds, but created a "disgusting" smell. Countdown Oamaru store manager Mandy Manpreet said at the time the roof had been cleaned nine times in the past 18 months to try to minimise the smell.
Department of Conservation (Doc) community ranger Andrew Powazynski, of Oamaru, said it could take "several years" to find a solution.
However, Dunedin-based researcher Dr Chris Lalas said he was surprised by the low number of red-billed gulls nesting this year across the North Otago town. After spending last Friday in town, he said a nesting site used by the birds at the breakwater at Oamaru Harbour appeared to have been abandoned.
At least as many red-billed gulls now seemed to be nesting on the buildings on the eastern side of Thames St, between Coquet and Wear Sts, and, overall, few birds appeared to be in town.
"I would be guessing it’s 200 birds all up — that’s low."
Dr Lalas said the gulls could have left the area to breed and would return to feed after the breeding season — or there could be 100 gulls breeding in "someone’s backyard" that he had not seen. A Countdown spokeswoman confirmed the store had, in consultation with Doc, used "stationary owls to deter other birds, and some limited use of sonic deterrents" to "carefully encourage the birds to nest elsewhere in the future given the impact they can have on the roof and building".
The department’s advice had also been to consider netting across the roof once all the chicks from this year’s nests had fledged and before the next breeding season in September.
Doc biodiversity ranger Brad Edwards, of Geraldine, said the department gave Countdown the authority under the Wildlife Act in May to take measures to disturb or prevent birds from nesting on its property.
"The birds returned to nest on the supermarket roof in September. However, due to Countdown’s efforts, fewer birds are nesting on the roof than previous years," Mr Edwards said.
"With the authority in place, Countdown can reduce the impact of the birds by clearing excess nesting material from the roof gutters and removing any dead birds. However, as the birds are protected, the birds, nests and eggs cannot be disturbed during the breeding season."
The breeding season runs from September to January.
Red-billed gulls are protected under the Wildlife Act. Numbers have declined more than 50% since 1994 and there are fewer than 100,000 of the birds left in New Zealand.
