To Mr and Mrs Blue, seven ducklings

Friends of the Cobb and the Department of Conservation are celebrating the arrival of the first whio (blue duck) chicks to have hatched in the Takaka River in many years.

The seven ducklings could be a turning point in the battle against stoats, the birds' main predators.

Friends of the Cobb have caught over 100 stoats in the wider area over the past two seasons in a bid to encourage whio to re-inhabit the river.

Along with Friends of Flora, who carry out similar work around Mt Arthur, the group received funding from the Tasman Environmental Trust's Cobb Mitigation Fund for the project.

"It's exciting news that we have a brood of seven blue duckling now about a month old on the Takaka River," said Alec Milne, a volunteer with Friends of the Cobb.

Mr Milne spotted the whio brood while checking stoat traps in the upper Takaka Valley.

"Kiwi also seem to be on the increase, with several recent reports from the Cobb Valley," he said.

He believes that intensive trapping in the lower Cobb Valley could be having a wider impact, with low stoat catches in the upper valley and no stoats caught in the Henderson Basin rock wren area this past season.

DOC ranger for threatened fauna Mike Ogle said stoats had decimated whio populations throughout New Zealand.

"Whio are nationally endangered and on the decline except in actively managed areas, where their numbers are increasing," he said.

Under a DOC whio recovery programme called Operation Nest Egg, whio eggs were taken from nests, and the ducklings raised and re-released last year in specially managed areas, including Rolling River and the Pearce River in Kahurangi National Park.

This week, DOC Golden Bay area office rangers are beginning a full whio survey covering dozens of kilometres of 20 rivers in the park.

The results will be used in conjunction with a survey carried out by the Motueka area office over the past two years.

There are an estimated 2500 whio in New Zealand.