High hopes for chicks
Despite food sources being below desired levels, the Department of Conservation is confident the first skrarks of kakapo chicks will be heard on Cod Fish Island since 2011, bolstering the numbers of the critically endangered species.
Male kakapo have begun booming to attract a mate on Cod Fish Island and DOC is expecting the ladies to respond to their advances.
There are only 124 known surviving kakapo on three New Zealand offshore islands.
Codfish Island, near Stewart Island, and Anchor Island, in Fiordland, are home to most of the remaining kakapo population, with a few birds on Little Barrier Island near Auckland.
After failing to breed during the past two seasons, a low rimu fruit count this season has again tempered expectations for staff at the Kakapo Recovery Programme.
Rimu fruit is an important food source for female kakapo and it was believed female kakapo used the availability of the fruit as a cue for breeding.
But conservation services manager for kakapo and takahe Deidre Vercoe said there were some rimu trees with good fruit supplies and if they were in a female's home range, some nesting could still occur.
''We are pretty sure breeding will occur and our guesstimate is between 5-10 nests.''
To listen to Kakapo boom click here
Unfortunately the lack of rimu fruit on Anchor Island had ruled out any breeding this season, she said.
The recovery team would also use artificial insemination to help boost the fertility of the eggs laid by breeding females, Ms Vercoe said.
''A semen top-up increases chances of a female having fertile eggs and we can choose the best genetics available for those chicks,'' she said.
About 40 per cent of all kakapo eggs laid have been infertile with another 20 per cent of embryos dying early in development.
It is suspected the underlying reason for this high infertility is inbreeding.Artificial insemination was successfully used during the programme's most prolific season in 2009 when two chicks from two females were born as a result of science.
Further scientific work on cryogenic preservation of semen would be done this season by international leaders in the field, Ms Vercoe said.
''If we can get semen samples and freeze them, in theory they can be stored for a decade then thawed to tap into the genetics of those males that have died,'' she said.
''We can freeze kakapo sperm but as of yet we have not been able to successfully use that frozen semen to AI a female.''
- The Southland Times
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