Old age probably killed Waynebo, the kakapo found dead on Codfish Island this month, the Conservation Department says.
Kakapo Recovery Programme manager Deirdre Vercoe said tests on his body had found no specific cause of death on January 2.
Although Waynebo had a small wound on his chest, the lack of inflammation suggested it had been inflicted after he was dead.
Found on Stewart Island in 1989 – making him one of the last discovered wild kakapo – Waynebo fathered 11 chicks during his time with the recovery programme.
"He was one of our stud birds," Ms Vercoe said. "He was a very good boomer and a strong breeder."
However, in the last two breeding seasons Waynebo's performance had declined and rangers thought he must have been getting on in years, she said. "He could have been over 100 [years old]."
Waynebo's death reduced the kakapo population to 128 birds.
It was a blow for the programme after two young females – Monoa and Purity – were also found dead in September last year.
There would be no breeding on Codfish this year because of a poor crop of rimu berries, the bird's staple diet, Ms Vercoe said.
"The boys are silent. At this time of year, they should be booming their hearts out."
In the past four years there had been three breeding seasons, which had boosted the number of the critically endangered animals to a high of 131.
- The Southland Times
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