Saturday, 26 July 2014


Gallirallus australis

Photo by Sid Mosdell (Wikipedia)

Common name:
weka (en); frango-d'água-austral (pt); râle wéka (fr); rascón weka (es); wekaralle (de)

Order Gruiformes
Family Rallidae

This species is endemic to New Zealand, being found in scattered location along the eastern coast of North Islands,  in the northern and south-western areas of South Island, in the islands of Chatham and Pitt, and in several islands around Stewart Island.

These birds are sexually dymorphic in size. The females are smaller with 46-50 cm in length and weigh 350-1.035 g, while the males are 50-60 cm long and weigh 530-1.600 g. They have a wingspan of 50-60 cm.

The weka uses most available habitats within their range, including temperate forests and grasslands, freshwater marshes and lakes and scrublands, and to a lesser extent coastal sand dunes, rocky shorelines and sandy or pebble beaches. They are present from sea level up to an altitude of 1.500 m.

They are omnivorous, taking both animals and plant material, including seeds, berries, leaves and grasses, as well as earthworms, adult and larval insects, snails and slugs, spiders, frogs, lizards, mice, small rabbits and small birds.

Wekas can breed all year round. They are monogamous and may pair for life. they nest on the ground, in dense cover such as tussocks, burrows, tree hollows, under logs, stumps or rocks, or even hidden in buildings. The nest is built by both sexes, consisting of a shallow cup made of woven grasses, lilies, twigs and moss, lined with finer grasses, feathers and hair. The female lays 1-4 eggs, which are incubated by both parents for 26-28 days. The chicks leave the nest 2-3 days after hatching, but remain under the care of the parents for about 2 months. They reach sexual maturity at 1 year of age and each pair may raise up to 4 broods per year.

IUCN status - VU (Vulnerable)
This species has a relatively large but fragmented breeding range, and the global population is estimated at 71.000-118.000 individuals. Although different sub-population may have different trends, the global population is suspected to be declining rapidly due to a combination of habitat clearance and degradation, road kills, a wide range of introduced mammalian predators and competitors, combinations of drought and flood years, poison baits used for possum and rabbit control, and possibly disease. Also, they have been eradicated from several islands due to possible risks to other native biota, and removal from Pitt and other islands is a future possibility.

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