Endangered tara iti/fairy tern: DoC celebrate most successful breeding season in eight years

Thanks to ongoing management of the birds and their habitats, the Department of Conservation believes there will be eight tara iti/fairy tern fledglings this year. Photo / DoC

Mangawhai sandspit and nearby beaches have turned into a bustling bird crèche as one of New Zealand's most endangered birds, the fairy tern, celebrates its most successful breeding season in eight years.

Eight tara iti (New Zealand fairy tern) are expected to fledge this year – a significant number considering there are fewer than 40 adult birds left.

The tara iti's official conservation status is nationally critical and despite extensive management, the population has teetered on the brink of extinction since the 1970s.

The Department of Conservation puts this season's success down to ongoing management of the birds and their habitats and strong support from volunteers as well as the wider community.

New care techniques from the Auckland Zoo and periods of settled weather have further helped the breeding parents.

DoC, alongside iwi and key stakeholders, has been developing a new recovery strategy for tara iti over the past few years.

This plan includes management of the vegetation, sand, and shells at the site to improve the quality of fairy tern habitats, and identify new sites for the birds.

Ongoing predator control, artificial incubation of eggs, and seasonal monitoring by DoC rangers and volunteers further support the population.

Once widespread around the North Island and on the eastern South Island, tara iti now nest at only four main sites, Papakānui Spit, Pākiri Beach and Waipū and Mangawhai sandspits. Photo / DoC

Rangers also try to prevent the fairy terns from nesting around exposed areas which could result in the loss of eggs and/or chicks as seen in previous seasons.

"By deterring the tara iti from nesting in this undesirable location we've seen them move to more stable areas nearby which are well protected from mobile sand during storm events," DoC biodiversity ranger Ayla Wiles said.

"Mangawhai is the most significant breeding site with six breeding pairs, and all bar one of these pairs successfully raised chicks this year."

For the past two years, Auckland Zoo has stepped in to help with the conservation efforts by conducting artificial incubating, hatching eggs, and hand-rearing chicks at the zoo.

Even though the team had very little experience or information on these techniques, they managed to successfully rear and release one chick last season. This year, there were five.

The chicks were transferred to the specially designed release-aviary on a beach where the birds occur naturally – two of which were successfully released.

In the aviary, the birds have the opportunity to practice flying and foraging for fish before being released to join the few remaining wild terns.

If these trials prove to be successful, then captive rearing may become an invaluable tool for improving numbers of tara iti, DoC says.

Rehabilitated Mid North kiwi chick being returned to the wild in February. Photo / Lesley Baigent

Meanwhile, Northland's brown kiwi are welcoming new offspring with the second batch of wild kiwi chicks hatching in nests all over the region during the last few weeks.

"This is a great sign suggesting adults were in good enough condition to be breeding three months ago," Far North Kiwi Coast co-ordinator, Lesley Baigent, explained in her nesting report.

"Despite having rain recently, the preceding dry weather has unfortunately not been kind to the chicks.

"The ground is still very hard, invertebrate numbers in the topsoil layers are low and some water sources have dried up."

Northland brown kiwi often nest twice during the breeding season if conditions are favourable.

At two eggs per nest, with sustained predator control, a good nesting season can boost the population numbers.

However, the timing of the stoat breeding season and dry summer can make conditions tougher for the second batch of kiwi chicks.

So far this season three chicks have been sent to the Whangārei Native Bird Recovery Centre for treatment.

"Dehydration and starvation can kill kiwi chicks quickly, so it is great local communities are looking out for these vulnerable guys and are acting fast," Baigent said.

Chicks are often out during the day and in some pretty unusual habitat but not all need help so do ask for advice before "rescuing" them.

The last chick was successfully released back into an intensively predator-controlled area in the Mid North recently after six nights in Whangārei where it was rehydrated and seen to be self-feeding well.