A tussock fire blazed for two hours and burnt about 1.5 hectares of land at Cape Sanctuary at Ocean Beach yesterday.
The blaze was located in an area which was difficult to access and was attended by appliances from the Havelock North, Hastings Heretaunga and Waimarama Brigades.
Hastings District Council principal rural fire officer Trevor Mitchell said the fire took two hours to control and left a large blackened area over the sand dunes. "The cause of the fire is under investigation but it is known that motorcyclists and other vehicles illegally access the area," he said.
Cape Sanctuary is located on three properties on the Cape Kidnappers Peninsula and is the largest privately owned wildlife restoration project of its kind in New Zealand.
The area is home to unique black and red katipo spiders, spotted skinks and is the only area of sand tussock on mainland New Zealand.
The owner of one of the properties on which the sanctuary is located, Andy Lowe, said it was "very disappointing" that the "valuable" area has been damaged by fire. Staff spotted two motorcyclists riding in the sand dunes on Wednesday, despite signage that warns endangered birds are nesting there.
Mr Lowe said the sanctuary is managed by volunteers and contains iwi sites of significance.
"This is a unique part of New Zealand where dotterels and oystercatchers are currently nesting and all I ask is that it is treated with respect. The area is available for everyone to enjoy and this type of damage really sets our development programme back."