Possum fur has been found on Kapiti Island just weeks after the Conservation Department believed it had eradicated stoats from the nature reserve.
A visitor found a tuft of possum fur near Rangatira Pt at the centre of the island on Saturday. It is being sent away for DNA analysis.
The Conservation Department began a $600,000 trapping and monitoring campaign on the island after a stoat was spotted there about two years ago.
Three stoats were found, but the department announced last month that it believed the island was now stoat-free. Department spokesman Rob Stone said at the time: "That does not mean there aren't any, but we are hopeful it is stoat-free."
Waikanae DOC office spokesman Colin Giddy said two dogs had just completed a search of the island and found no sign of stoats. Dogs would return in February when any young stoats would be out and about by themselves.
It was believed the fur found during the weekend was from a possum, he said. "If it was one male possum, or one pregnant female carrying a female young, it would not be a huge concern. But if it was a pregnant female carrying a male, there could be three possums within about two years."
Parts of rats' bodies had been found on the northern end of the island in the past, but they were believed to have been regurgitated by gulls, who had a colony nearby.
"It could be something like that: a dead possum washed up on shore. It is a blessing for us they are not great breeders," Mr Giddy said.
Stoats could have up to 12 young at once, while possums generally had one.
Introduced mammals were eradicated from the island in 1996. Kapiti Island is a wildlife sanctuary for some of the country's rarest native birds, including the little spotted kiwi, stitchbird and takahe.
- The Dominion Post
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