The Department of Conservation is concerned that hundreds of helium balloons released by The Warehouse to celebrate its 25th birthday have washed up on Great Barrier Island.
Apart from the visual pollution there is concern that wildlife might mistake the balloons for food.
The 13,000 balloons were released two weeks ago from Dairy Flat.
An Auckland woman visiting the island a fortnight ago was shocked to find hundreds of the balloons around the high-tide mark of Kaitoke Beach on the east coast.
DoC yesterday confirmed 10 balloons had been found at Mabey's Beach to the north.
Alison Craig said she had picked up 132 of the balloons, which resembled little quivering squid, from the beach in just half an hour.
There were hundreds more on the beach, which surprised her, given the remoteness of the beautiful and usually unblemished coastline.
Alison Turner, community relations officer for DoC on Great Barrier, said people on other Hauraki Gulf Islands would be asked to notify any sightings to determine the extent of the balloon pollution.
Tony Bouzaid, the chairman of the Great Barrier Community Board, said the balloons must have drifted over the island and possibly far out to sea before washing back in.
A spokesperson for The Warehouse was concerned that some balloons were found on Great Barrier Island but disappointed the company was not informed sooner.
"Had we known, we would have addressed the issue. We ask anyone who finds anything that may have been from the exercise to let us know so that we may work to correct the situation."