First fairy terns eggs of season laid at Northland's sandspits

This photo by Malcolm Pullman of a nesting fairy tern at Waipu was used on a New Zealand postage stamp in 2014.

One of New Zealand's rarest birds has surprised Department of Conservation rangers by producing eggs in October, a little earlier than usual.

With a total population of approximately 40 birds, the New Zealand fairy tern - or tara-iti - is critically endangered and has teetered on the brink of extinction since the 1970s.

A dedicated protection effort has seen the species breed just successfully enough each season to keep its precarious numbers constant.

"Our fairy tern team has been preparing for the breeding season for a few months and we are thrilled to have eggs in nests,'' said DoC fairy tern team ranger Ayla Wiles.

''One of the earlier nests was lost early on, but three remain. We are hopeful the nests will be successful and the chicks will fledge by Christmas.''

Fairy tern nests are made in shallow scrapes on shell and sand banks just above high tide which leaves them vulnerable to predators, disturbance by people, 4WD vehicles and dogs. They are also at risk from stormy weather and very high tides.

"There are three pairs of fairy tern with active nests which have one or two eggs each," Wiles said.

"The parents take turns sitting on the egg for about an hour at a time and will do this 24/7 until the chick hatches in early November,'' Wiles said.

A dedicated team of five fairy tern DoC rangers have been busy since September trapping predators near nesting sites and preventing nesting birds from being disturbed by humans.

Once widespread around the North Island and on the eastern South Island, the small bird now breeds at only four nesting sites: Pakiri Beach, Waipū and Mangawhai sandspits in Northland and Papakanui Spit, near the south head of the Kaipara Harbour.

DoC works closely with hapū Patuharakeke and Te Uri O Hau, Te Arai and Mangawhai Shorebirds Trust, NZ Fairy Tern Charitable Trust, About Tern, Birds NZ, Armourguard and the Waipū Trapping Group to help protect the fairy tern.

Beachgoers are asked to also help by staying out of fenced areas and using designated walkways, avoid shorebird nests and chicks, keeping dogs on leads, removing bait, fish and rubbish to deter predators and running vehicles below the high tide mark.

If people walking a sandspit are chased, squawked at, or if a bird is on the ground pretending to be injured, they are too close to a nest. No dogs or vehicles are allowed in wildlife refuges and reserves, and disturbance of wildlife is an offence.