Remnants of human habitation on New Zealand's remote Campbell Island are at risk of being wiped out.
Aucklander Norm Judd, who has visited the island nine times since 1975, said Hooker's sea lions and scrub growth could destroy the sites before there was an opportunity for a thorough examination.
Scrub has been rapidly regenerating on Campbell Island since wild sheep were removed in 1991. It is covering traces of early encampments.
Judd and three archaeologists are preparing a business case to persuade the Department of Conservation to fund a summer expedition to clear vegetation and fence sites. "Future archaeological work will get extremely difficult unless we act soon," Judd said.
During the 1970s, Judd interviewed two men who worked as farm labourers on the island almost 100 years ago.
Those interviews helped locate the grave of a young French sailor, who visited with a scientific expedition in 1874.
"I realised we'd only scratched the surface," Judd said.
"Kiwis know a lot more about the birds and marine mammals on Campbell Island than about its past human inhabitants.
"We know little about the shipwrecked castaways, explorers, sealers and whalers who once lived there."
He said someone smashed rocks — most likely for use as cutting tools - and these are on the beaches and at Tucker Cove.
"Professional sealers had knives, so who was skinning seals with these sharp stones? Was it castaways who had moved into abandoned sealer huts or did Polynesian explorers arrive before the sealers?
"We don't even know for sure when the first Europeans arrived on Campbell Island.
"Accepted wisdom is that it was in 1810, when the sealing brig Perseverance arrived. But another European ship, or ships, may have been earlier."
DoC spokesman Brent Beaven was unsure the department had sufficient resources to act on Judd's request.
"Norm put a submission to our conservation strategy and I've since had discussions with him," said the Invercargill-based conservation manager for southern islands.
"I've taken his concerns on board and don't disagree with them in the slightest. I've contracted somebody to look at Norm's intentions and am keen to try to do more Sub Antarctic work, if possible," he said.
Judd said a future party of archaeologists could make a major discovery and rewrite history books.
"But my fear is, unless we act soon, future expeditions will have little or nothing left to work with."