“This suggests to us this bird might have been killed by a predator,” she said.
“Tuturuatu are highly susceptible to predation — a single rat can wipe out an entire population.
“This makes biosecurity and pest control highly essential to protect this species.”
With only 250 left in the wild, the tuturuatu is critically endangered, with the last naturally occurring population found on the remote Chatham Islands.
However, thanks to the captive breeding programme at Pukaka Mount Bruce and the Isaac Conservation Wildlife Trust, birds can be sourced to populate suitable new locations.
Ms Norgate said Waikawa had proved to be such a location.
“With limited predator-free offshore islands with appropriate habitat, places like Waikawa are incredibly valuable for the future of this species.
“The more securely and safely the population can be built up will mean this species has a better chance of survival.
“It also means every single one of these birds count if we are going to save them from extinction.
“It reminds us that projects such as Predator Free 2050 are more important than ever.”
Ms Norgate said the public should report tuturuatu sightings to Nature Watch at naturewatch.org.nz or to their local DoC office.
“If you can observe the colours of the leg bands, that can provide a lot of useful information to us.”