Regional council staff are planning to head out to a string of islands off Northland's east coast today to make sure a serious threat to wildlife has been properly cleaned up.

The owners of Motukawaiti Island, about 3km off Matauri Bay, had been given until midnight last Thursday to remove countless fragments of polystyrene scattered across the scenic Cavalli Islands. The material, which can be fatal if swallowed by marine life such as birds, fish and dolphins, came from a pontoon which broke free and was smashed apart in last month's cyclone.

The Northland Regional Council issued an abatement notice on April 17, giving the pontoon's owners a week to clean up the mess.

A kayaking group approached the Advocate last week Tuesday after being horrified by the extent of polystyrene pollution, particularly on Kahangaro and Motukawanui islands. They found several large slabs 1m thick and countless tiny pieces piled up on the beach and blowing up the hillsides like snowdrifts.


Regional council coastal monitoring manager Ricky Eyre said the island's owners had employed a Northland contracting firm, which started the clean-up on Wednesday with petrol-powered vacuum pumps and ''lots of hands on deck''.

The company that owned the island had been cooperative, he said.

Council staff were planning to inspect the islands on Monday to make sure they had been fully cleaned up.

If the abatement notice was not complied with the council could impose a fine, ''but fingers crossed it doesn't come to that''.

When first reported by dive operators three weeks earlier the polystyrene was confined to one small island.

By last week it was spread across several islands and was being reported as far away as Tapuaetahi, just north of the Bay of Islands.