Six volunteers from the Pomona Island Charitable Trust spent last week on the remote Breaksea Island, off the Fiordland coast, catching the friendly and easy-to-see black with white-breasted birds for transfer to bush-covered Pomona and Rona Islands.
Volunteers and Department of Conservation staff caught their feathered friends by placing nets upright with meal worms in front and flipping the nets over when the birds swooped in.
Trust secretary Viv Shaw, of Te Anau, said it was "very satisfying" to release the robins after the rats, mice, stoats, possums and deer were eradicated from the habitats.
Up to 30 robins were transferred to Pomona by helicopter early in the week, with another 10 released by boat a few days later.
A further 11 birds were released on Rona Island.
The transfer was made possible by a $5000 donation from an anonymous benefactor.
The entire operation cost about $7500, which was met by donations to the trust and its Friends of Pomona scheme.
"This was the first transfer of birds to Pomona and Rona Islands so it was particularly exciting," Dr Shaw said.
"We hope that it will be the first of many translocations of birds to these islands."
Dr Shaw said the trust planned to transfer more threatened species in the future, including saddleback, mohua and kiwi.
They hope to organise a second transfer next year.
As open sanctuary islands, the public can visit Pomona and Rona at any time.
Dr Shaw said the trust needed the help of the community to keep the islands pest-free.
"Anyone intending to visit the islands should check their boats and packs for rats, mice and seeds. No pets are allowed and visitors should take all their rubbish away.
"The islands are an asset for the community and provide an accessible location where people can see, hear and learn about Fiordland's flora and fauna."
