The hatching of the first eggs of a critically endangered species of seabird on the Chatham Islands is being heralded as a major milestone for the bird's conservation.
The Chatham Islands taiko (magenta petrel) is one of the world's rarest seabird species, with only 14 known breeding pairs in the predator-free environment in Sweetwater Conservation Covenant.
All 57 known taiko chicks were transferred to Sweetwater between 2007 and 2011.
Sweetwater is a 2.4 hectare forest protected by an 800-metre predator-proof fence on private land owned by Bruce and Liz Tuanui, who covenanted the land for taiko conservation in 2004.
The Taiko Trust has been monitoring taiko in Sweetwater Conservation for the past three years, but this is the first breeding attempt because the birds do not breed until they are between five and seven years old.
Taiko Trust chairwoman Liz Tuanui said the breeding population in Sweetwater was expected to continue to increase in the next five years.
"The hatching of these first two taiko eggs in Sweetwater is a major milestone for the conservation of this critically endangered species."
A high proportion of chicks returning to the forest was also positive, Tuanui said.
"Not only have two pairs started breeding, but 70 per cent of translocated chicks from the first two years of translocations have returned.
"This is significantly higher than the 30 per cent recorded in the natural population."
Taiko Trust monitoring had shown pre-breeding taiko spent between three and six hours a night on the ground, calling and exploring the area as they looked for burrows and partners.
In an unprotected environment this would make them very vulnerable to predation, so the Sweetwater environment was advantageous in increasing the species' population, Tuanui said.
"The number of birds being recorded in Sweetwater bodes well for the future, the predator-free environment allows the birds to court, find partners and start breeding without the risk of predation.
"Our return rate indicates that preventing predation during the pre-breeding stage is critical," she said.
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