#notornis

[scottpartridge]

Day 16 of #migratorymay2025 hosted by @migratorymay is the #Takahe of New Zealand, the largest rail in the world these days, although fossils indicate there was once a larger one known as the North Island Takahe.

[drhoz]

#2744 - Porphyrio hochstetteri - South Island Takahē 

Quammen and Paku, the breeding pair at Orokonui Ecosanctuary, and two of their chicks.

AKA Notornis mantelli hochstetteri and Porphyrio mantelli hochstetteri.

A flightless Rail, and the world's largest living species in the family. Endangered, and believed hunted to extinction by 1898, then rediscovered in 1948 around Lake Te Anau in the Murchison Mountains. The North Island Takahē or Moho (Porphyrio mantelli) didn't have the same luck.

They lost most of their lowland habitat as swamplands were destroyed for agriculture, and in the wild now live only in alpine tussock grasslands, moving down into forests in winter. Deer remain serious competitors, leading to culling programs in the Murchisons.

Breeding pairs have been sent to refuges around the country, to try and preserve the species should anything else befall the wild birds. Inbreeding even in the wild population has unfortunately lead to serious fertility problems, on top of their slow reproductive rate.

Orokonui Ecosanctuary, Aotearoa New Zealand

[ainawgsd]

Takahe

The South Island takahē, notornis, or takahē (Porphyrio hochstetteri), is a flightless bird indigenous to New Zealand and belonging to the rail family. It was thought to be extinct after the last four known specimens were taken in 1898. However, after a carefully planned search effort the bird was rediscovered near Lake Te Anau in the Murchison Mountains, South Island, on 20 November 1948. 

The adult takahē is mainly purple-blue in color, with a greenish back and inner wings. It has a red frontal shield and red-based pink bill. The legs are pink. Sexes are similar, the females being slightly smaller, but young birds have mainly pale brown plumage. Immature birds have a pinkish bill with a bluish cast. This is a noisy species with a loud clowp call. 

The species is still present in the location where it was rediscovered in the Murchison Mountains. Small numbers have also been successfully translocated to five predator-free offshore islands, Tiritiri Matangi, Kapiti, Maud, Mana and Motutapu, where they can be viewed by the public. As of October 2016 there were 306 takahē accounted for, showing slow but steady growth over the previous few years.

The takahē is monogamous, with pairs remaining together from 12 years to, probably, their entire lives. It builds a bulky nest under bushes and scrub, and lays one to three buff eggs. The chick survival rate is 73-97%.

The near-extinction of the formerly widespread takahē is due to a number of factors: over-hunting, loss of habitat and introduced predators have all played a part. The introduction of red deer (Cervus elaphus) represent a severe competition for food, while the stoats (Mustela erminea) take a role as predators. Since the species is long-lived, reproduces slowly, takes several years to reach maturity, and had a large range that has drastically contracted in comparatively few generations, inbreeding depression is a significant problem.