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Kakas - a precious taonga
by Liz Westbrooke
 

KRAAAK! Kraaak! Kraaak! They fly over our place almost every night in the summer at around 7pm. Like a motorcycle gang, but dressed in olive brown rather than black leather, they zoom up the valley from the seacoast straight through the gap between us and Little Windy Hill. Then on down to Tryphena I guess. We usually see about five at once, however other residents up here have seen as many as eleven.

They look and sound tough with their screeching but are actually increasingly vulnerable. Last year kaka were upgraded to Status 2 – Nationally Endangered. That rating has put them up there with brown teal and chevron skinks. There is only one higher score and that is Critically Endangered, a status reserved for birds like the kakapo, dangerously close to extinction for half a century.

So we are very lucky to have them here! I know it doesn’t feel like that when they attack our fruit trees (but more on that later).

Kakas are practically extinct as a breeding bird on the mainland existing only where there are ‘mainland islands’ with targeted predator programmes (or fences) such as Mt Bruce, Pureora Forest and the Karori Sanctuary. Indeed both Mt Bruce and Karori are captive breeding kaka in their endeavours to re-establish a wild kaka population. It has taken ten years of effort at Mt Bruce to get the kaka numbers up to around 75.

I found no research available focused on Great Barrier kaka and why they remain viable here. But it appears that the absence of stoats (and possibly Norway rats) allows nesting females and chicks to survive better in their deep hollow-tree nest sites. Recent nationwide research found that possums too feast on both eggs and chicks and will even kill adult females. So the absence of possums on Great Barrier Island is also a positive factor. Of course we still have the problem of feral cats and rats.

Young kaka are practically flightless for several days after they leave the nest though they can climb quite well. Kaka lay their eggs through spring and early summer and these take 24 to 26 days to incubate. The female does all the sitting on eggs and is fed every hour and a half by the male (great room service!). The nestlings take about another 10 weeks before they fledge and these ‘babies’ are not fully independent from the adults for a further 5 months. Quite a parenting effort!

If like us you have regular kaka visitors, then you are very likely seeing the same birds over and over – adult kaka generally have a relatively small home range. They do go on excursions however and movements of over 30 km have been recorded for newly fledged birds which take a while to settle. Recent bird counts carried out by the Trust on Great Barrier found kaka distributed throughout the island – they were seen in pasture, estuary, kanuka/manuka, lowland bush and montane bush eco-systems.

 

So what can you do to help this highly endangered bird survive?

• keep your dogs on a leash especially in any bush areas where there may be fledglings on the ground or nests low down;

• net your fruit trees – but this must be sturdy and may only work if made of wire to stop the birds eating their way through;

• some other suggestions for your garden are to use bird scaring devices such as raptor kites, hazing tape or streamers or playing recorded alarm calls – so try these out – or simply accept that a portion of your fruit is going to a good cause;

• get your pet cat spayed or neutered to ensure there is no likelihood you unwittingly add to the feral cat population;

• keep a diary of your observations of these fascinating birds;

• leave your pets at home if you are a holiday maker, or keep them very well managed on the island;

• be very careful if you are visiting or returning to the island not to bring any unwanted ‘visitors’ (possums, stoats, ferrets, Norway rats) with you or your luggage, car, freight or boat;

• Kaka breed most successfully after a good season of kahikatea or rimu seed production so if you are planting something new, consider one of these native trees.

 

REFERENCES:
Birds of Aotearoa: A Natural and Cultural History.
Margaret Orbell. Reed 2003.; 

Biodiversity Advice Fund Report 1. John Ogden. 2006; Biodiversity Conservation DOC Fact Sheet Feb 1997; Field Guide to the Birds of New Zealand, Heather & Robertson, 1996 Viking; Great Barrier Island, Canterbury University Press, 2001;

New Zealand Birds, Geoff Moar, Reed Field Guide 1992; Personal Communication, Halema Jamieson; Personal Communication, Raelene Berry; Research summary and options for conservation of kaka (Nestor meridionalis). T.C. Greene et alia. DOC Internal Science series 178, 2004.

WEB SITES:

• www.terranature.org/parrots

• www.mtbruce.org.nz   kaka_captive_more

• www.doc.govt.nz/Conservation/  001~Plants-and-Animals/  006~Threatened-species/Bird

• www.iucnredlist.org/search/  details.php/14728/summ