Mr Langsbury, who chairs the Otago Peninsula Biodiversity Trust and is a trustee of Predator Free Dunedin, said he had previously seen some well-fed feral cats, and wanted to learn more about the recent sighting.
Some larger than usual feral cats — probably well fed from eating the abundant rabbits on the peninsula — potentially posed a larger than usual threat to native birdlife and penguins, he said.
Dunedin primary school teacher Jacqui Russell said that at 7pm on Wednesday, she was walking on a farm west of Allans Beach, about 1km from the beach.
She saw a large, well-fed feral cat, two to three times the size of any domestic cat she had ever seen, standing among trees in a pine plantation, between the farm and the beach.
She was holding a camera, but "in my shock I was so dumbstruck I never thought to take a photo" of the large tawny creature.
"I was in a state of being unable to believe my eyes," she said.
Having seen the unusually large cat, she was now more inclined to believe other people who had reported seeing large cats in the South Island over the years, she said.
Last weekend, Christchurch osteopath Mark Orr reported seeing a panther-like cat while he was mountain biking at Hanmer Springs.
Former peninsula trust marketing manager Sophie Barker said she "wouldn’t be surprised" if Ms Russell had seen a larger than usual feral cat, and she had also seen some big feral cats.
The Department of Conservation says some feral cats can grow much larger than the average house cat and have a "major impact" on native birds, lizards and insects.
