Causes of extinction are complex, and are likely to be due to interactions between climatic conditions (especially drought) and predator numbers (especially ferrets, stoats and dogs).Fortunately, weka still thrive at many accessible sites, including on Kawau, Mokoia, Kapiti, Ulva and Chatham Islands, the Marlborough Sounds, North Westland, and parts of the Abel Tasman, Heaphy and Milford Tracks.All South Island mainland populations (apart from Totaranui, Golden Bay) and remaining island populations in the Marlborough Sounds are natural, while all remaining populations on Stewart Island, on most of the islands surrounding Stewart Island, and on the Chatham Islands are introductions. Breeding The timing and number of clutches per annum varies between some pairs producing multiple clutches per annum, to intermittent breeding once every few years. Weka are often killed by uncontrolled dogs, and are legally hunted on the Chatham Islands and on some muttonbird islands. Most birds have their dorsal feathers streaked with black, and all have their longest wing and tail feathers boldly barred with black.Weka have been eradicated from many islands where they had been introduced to, due to their predatory impacts on other fauna, especially burrow-nesting seabirds, ground nesting birds, reptiles and large invertebrates. Other calls include booming, and soft clucking contact calls.Similar species: the banded rail is much smaller and more boldly marked, including a rufous eye-stripe on an otherwise pale grey face, a broad orange breast band, and underparts boldly barred with black-and-white.
Threats and conservation The main recognised threats are starvation during droughts, and predation by mustelids, especially ferrets. Length: 50 - 60 cm Weight: 430 - 1400 g Similar species: Banded rail, Common pheasant A large flightless rail with red eyes, a strong pointed reddish to greyish bill, red strong legs and variable plumage ranging in colour from greyish and mid-brown to chestnut brown and almost black.Female common pheasants have smaller heads, shorter bills, much longer tails, and will fly if pressed.Distribution and habitat Weka strongholds include Russell Peninsula, Kawakawa Bay and Opotiki-Motu in the North Island, and the Marlborough Sounds, North-west Nelson, the West Coast north of Ross, and Fiordland in the South Island.Also many islands including Kawau, Rakitu, Pakatoa, Rotoroa, Mokoia, Kapiti, D’Urville, Arapawa, Chatham, Pitt, Ulva, Ruapuke, Solander and many muttonbird islands near Stewart Island.All North Island populations apart from Kapiti Island are North Island weka, all South Island populations from Marlborough Sounds to Fiordland are western weka.