Famous as the breeding ground of the migratory mutton birds (titi), the islands are also becoming the home to an increasing number of fur seals.
Department of Conservation southern islands area manager Andy Roberts, of Invercargill, confirmed the department was working with the mutton-birders and "was hoping to get a monitoring trip under way in March".
"When a native species is causing a problem with another, we have to figure out what to do."
Fur seals were hunted to the brink of extinction by early settlers, but the population of mammals had increased markedly since granted full protection in 1894.
Conversely, their numbers were now affecting mutton birds, an important source of food and income for a small group of southern Maori who have exclusive harvesting rights on the 36 islands making up the Mutton Bird Islands, around Stewart Island.
Mutton-birder Michael Skerrett said the fur-seal population was the largest he had seen in the 56 years he had been going to the islands - and feared it would get worse.
"There is no doubt that they are a real problem.
"Back when I was a kid, you would never notice them . . . not like now."
Not only were the fur seals destroying vegetation and nesting burrows, they were also hiding under properties and becoming territorial about their new homes.
A cull appeared the likely option to address the problem, Mr Skerrett said, but the onus would be on the committee to provide the research to verify the fur-seal problem with Doc.
That could be a number of years away.
"We are not talking about extermination; more about management."
Rakiura Titi committee chairman Robert Coote said fur seals were destroying the birds' burrows as well as the vegetation as they moved from the beaches to the bush.
The committee had discussed the growing seal problem and had approached several groups about funding a possible study aimed at providing a solution.
It was possible the University of Otago, which had conducted studies on mutton birds in the past, would be involved in the project, he said.
Asked if culling was an option, Mr Coote said the committee would have to sight the study's finding before a formal approach was made to Doc.
Although the number of birds often fluctuates in a season - two years ago was one of the best on record but this season was one of the worst - the growing population of fur seals appeared to be affecting their population, he said.
