Two more birds have been found dead on the same Dunedin beach where three birds were earlier found dead or fatally injured and surrounded by vehicle tyre tracks.
Bird Rescue Dunedin founder Sue Cook says the deaths were "definitely deliberate".
It follows about 30 protected red-billed gulls being killed at Taiaroa Head about a week ago, after two cars and a quad bike were seen on CCTV careering around the Royal Albatross Centre car park.
The first three birds — a dead little penguin, a dead black-backed gull and severely injured black-backed gull — were found at Waldronville Beach on Saturday, surrounded by vehicle tyre tracks and recently extinguished campfires.
Yesterday, a wildlife volunteer returned to the scene to investigate further.
They found two dead shags, also surrounded by tyre marks.
Cook said the incident had been distressing for both the wildlife and those who had to find the dead and injured animals.
"The lady that found the first gull had a 6-year-old boy with her. The gull was still alive and trying to pull its head up, and the wee boy was in tears."
The gull was later euthanised due to its injuries.
Following the deaths, Bird Rescue Dunedin was contacted by a woman who said she had found a heron, a black-backed gull and a few other birds earlier this month, also dead and surrounded by tyre tracks on Waldronville Beach.
"This has happened before, the same place, the same tracks," Cook said.
"It was definitely deliberate."
She hoped locals might have seen something that could help track down the people responsible.