Dogs - along with human intervention - appear to have caused the deaths of blue penguins at the Oamaru Creek penguin refuge in recent weeks.
Yesterday, Department of Conservation ranger Kevin Pearce said it was disturbing that a person or people might have been involved.
He was contacted two weeks ago by environmentalist Lorraine Adams, who found several dead penguins at the harbour refuge, which runs north from Holmes Wharf to Oamaru Creek.
Some of the nest boxes contained stones to prevent the birds getting out, there were lids off boxes and dead penguins still in boxes.
On Tuesday, staff at the Oamaru blue penguin colony told Mr Pearce five dead birds had been found during monitoring at the refuge.
Some of the nest boxes had been scattered and were lying a few metres from the dead birds.
Several of the birds were in the corner of their nests as if they had been trying to escape.
Mr Pearce was organising an autopsy yesterday but he was ‘‘99.9%'' certain that dogs were responsible.
The ‘‘scary part'' was that people appeared to have been involved, with someone obviously removing the boxes after the birds had been killed and, in the first incident, the stones placed in the entrances to prevent them getting out.
‘‘It's a concern to me there's obviously been human intervention, along with the dog kill. There's no way dogs would have done the destruction that was there,'' Mr Pearce said.
He implored members of the public to take care if they were in the harbour area with dogs and make sure they were on leads and under control. The refuge was not open to the public.
If anyone saw dogs in the area or any suspicious activity they should contact Doc, the blue penguin colony or police.
It was unfortunate the refuge was in an isolated area and therefore vulnerable to people walking with dogs or to stray dogs, he said.
Under the Wildlife Act, anyone charged with robbing, destroying or disturbing a nest could face up to six months imprisonment or a fine of up to $250,000.
