#callaeas

One of two species of Callaeas, the type genus for the New Zealand wattlebirds, the Callaeidae. unfortunately, they're also the only remaining species in the genus, since the South Island kōkako (Callaeas cinereus) is probably extinct, and this one pretty damn close to following it. The other three Callaeids being two species of tieke (saddleback) and the extinct huia.

Previously widespread, kōkako populations throughout New Zealand were decimated by possums, stoats, cats and rats.

The genus Callaeas was introduced in 1788 by the German naturalist Johann Reinhold Forster. The genus name is derived from the Ancient Greek word kallaia for a cock's wattles.

The family is believed to be a remnant of an early expansion of passerines into New Zealand, and have no close relatives apart from the stitchbird or hihi (Notiomystis cincta), and their taxonomic relationships to other birds remain to be determined. Assuming any of them survive long enough to answer the question.

Their diet includes leaves, fern fronds, flowers, fruit and invertebrates, and they are poor fliers. The kōkako has a clear, organ-like song, audible for kilometres - breeding pairs sing together in a bell-like duet for up to an hour in the early morning.

In one notable Māori myth, a kōkako gave Māui water as he fought the sun by filling its wattles with water and offering it to quench his thirst. Māui rewarded kōkako for its kindness by stretching its legs until they were lean, long and strong, so that kōkako could easily leap through the forest to find food.

The kōkako appears on the reverse side of the New Zealand $50 note

The Kokako an endemic and endangered bird of New Zealand

The Kokako, belonging, with the extinct Huia and Tieke, to the ancient wattlebird family Callaeidae, is endemic to New Zealand. The common ancestor of these birds probably became isolated when the super continent, Gondwanaland, began to fragment some 80 million years ago. These birds are found nowhere else in the world, nor do they have any obvious living relatives. 

Callaeas cinereus is predominantly blue–grey, the bill and legs are black along with a distinctive velvet black mask. The North Island species has ultramarine wattles under the throat. The South Island bird has orange wattles but this bird is now believed to be extinct [1]. 

Kokako populations are declining and the species is currently regarded as Endangered on the UICN Red List. The combination of deforestation and the introduction of invasive mammalian predators nearly extirpated this species. Ship rats, brush-tail possums, stoats and wild cats, prey heavily on young and female kokakos at the nest, leaving an excess of males who are not able to breed. These males sometimes pair up and nest with each other in the absence of female partners [2]. 

In 2008 the global population contained 769 breeding pairs. The number of mature individuals is higher, but the population has a surplus of adult males, thus the effective population size is lower. It is estimated to number at least 1,000 mature individuals, equivalent to 1,500 individuals in total [3].