Weather hampers survey of ko¯kako
The notorious wet and windy spring season is playing havoc for ecologists undertaking an annual ko¯ kako breeding survey in North Taranaki.
‘‘The rain and wind has made it hard for us to locate the birds, who become less responsive to the recorded bird calls played to them,’’ ecologist Joel Henton said.
Henton is monitoring the endangered species for Tiaki Te Mauri o Parininihi Trust during the summer breeding season, between November and March, at Parininihi, 50km north of New Plymouth.
He used a speaker to play a recorded song, usually of a ko¯ kako from the same area, to the birds.
‘‘We have found the ko¯kako will respond to their own dialect,’’ he said.
‘‘Because we can’t hear them respond to our recorded calls, it makes it more difficult to find them,’’ he said.
Forty-five ko¯ kako have been translocated from Pureora Forest and Tiritiri Matangi and released into the Ngati Tama iwi-owned bush reserve in the past three years.
Henton was also searching for nests to gauge the birds’ breeding success.
So far one active nest had been found.
‘‘Searching for nests is a bit more complicated. We know where the banded birds which have paired up are but it is a bit like putting a jigsaw together,’’ he said.
‘‘If we see a female we know there is nest close by and it will be more common to find a nest with the female sitting on the eggs.’’
Because of an 18-day incubation period where the female will be on the nest, it is also likely only the male bird will be found, he said.
‘‘We have seen around every
30 minutes the male will go to the nest to feed the female who can be either on, or off the nest,’’ he said.
‘‘She will come off the nest about every hour, and the feeding will take about 5-15 minutes.’’
Henton visits the reserve every fortnight during the breeding season, and has found two nests so far.
‘‘One nest had been attacked by predators, or ‘failed’, and no eggs were found in the other nest,’’ he said.
The breeding cycle is over a
50-day period, with ko¯ kako able to produce two ‘‘clutches’’ a season.
There have been 13 fledglings leave the nest in the past two breeding seasons at Parininihi.
Predators, mainly rats and cats, continue to prove a problem at Parininihi.
Tiaki Te Mauri o Parininihi Trust project leader Conrad O’Carroll said trapping was helping the small volunteer group make progress on predator numbers.
‘‘Overall the ko¯kako population is surviving but feral cats are a real problem attacking nests and we’ve lost a couple of birds to predators,’’ he said. puzzle