A team of Department of Conservation rangers and volunteers work year-round to protect the tara iti nests, including trapping predators, create safe nesting environments and prevent disturbance near nesting sites.
Now, DoC and partners have made a breakthrough in endangered species conservation by using 3D-printed replica eggs to safeguard the nests, helping the birds have a record-breaking breeding season.
The replica eggs are used as a management tool during high-risk periods - such as storms and high tides - allowing the adult birds to continue incubating while their real eggs are temporarily held in incubators or moved to safety at Auckland Zoo.
Initially, DoC used hand-painted wooden eggs, followed by real eggs with hollow interiors filled with wax. However, these methods presented challenges as the eggs became fragile over time.
In 2023, with funding from the Endangered Species Foundation Tāngaro Tuia te Ora, DoC commissioned Shaun Lee to produce 3D replica eggs, which were then hand-painted by artist and marine biologist Carina Sim-Smith.
The replica eggs have undergone meticulous design considerations including shape, weight, UV resistance, size, colour and texture.
The resulting eggs are so close to the real thing tara iti parents are completely oblivious when they were swapped out.
The replica eggs, and broader tara iti conservation, has led to a record-breaking breeding season this summer, with 22 eggs laid and 14 chicks successfully hatched.
DoC Whangārei biodiversity ranger Ayla Wiles said DoC is lucky to have the support of the Endangered Species Foundation to produce the 3D eggs, which are a crucial management tool.
“They allow us to improve productivity and save nests without losing real eggs in the process,” Wiles said.
Two 3D-printed replica eggs hold a tara iti/NZ fairy tern nest at Mangawhai - one of just five sites where the critically endangered shore birds now breed. Photo / DoC
Foundation general manager Natalie Jessup said it had been heartening this year to see the progress DoC, volunteers, community groups and Auckland Zoo have made to boost numbers of the tara iti.
“We were happy to see the replacement eggs were successful at holding nesting sites during risky periods when the real eggs were safely cared for at Auckland Zoo - they were so realistic parent birds had no idea they were not sitting on the real thing.”
The tara iti were once widespread but now only breed at Waipū and Mangawhai sandspits, Papakānui Spit in Auckland’s South Head, Pākiri Beach and Te Ārai Stream mouth.
DoC collaborates closely with partners including Patuharakeke, Ngāti Wai, Ngāti Whātua o Kaipara, Ngāti Manuhiri Settlement Trust, Auckland Zoo, the Shorebirds Trust, the NZ Fairy Tern Charitable Trust, About Tern, Birds NZ, Tara Iti Golf Club and the Waipū Trapping Group.
The programme is also supported by Pākiri Beach Holiday Park, Tara Iti Golf Club, Auckland Council, Manāki Whitebait, Tongariro National Trout Centre and New Zealand King Salmon.
