#adzebill

One of three species in the now extinct family Aptornithidae - the other two were the North Island adzebill, (Aptornis otidiformis), and a possible species Aptornis proasciarostratus from the remarkable Saint Bathans fauna of the Miocene.

A large omnivorous bird of uncertain affiities, originally described as a small Moa, that lived in dryer more open country. Unlike the last few species I've covered, this one was already extinct before Europeans showed up - the Māori name was "ngutu hahau", presumably when they weren't calling it "lunch".

The photo above is of a reconstruction on display at Te Papa, the national museum in Auckland. There are no records of the colour of the living birds.

Oc-tober day 20: Adzebills.

The Moa-keeper has some difficulty with wrangling a few of the birds. The chief troublemakers in the property are her two Adzebills: Toki and Koko. Here she is wrangling Toki who had somehow escaped their pen. Again. She has to take them back to where they belong.

Island Weirdness #35 — Flightless Giants

With the lack of large terrestrial mammals in New Zealand, birds were free to exploit the "big herbivore" niches in the ecosystem — and the giant moa were the ultimate result.

Closely related to modern South American tinamous, the ancestors of moa were small flying birds that arrived in New Zealand sometime in the early Cenozoic. At the time of the Miocene St Bathans fossil deposits they were already large and flightless, and by the Holocene they had grown truly enormous.

Uniquely they completely lost their wings, not even having the tiny vestigial bones seen in other large flightless birds.

The South Island giant moa (Dinornis robustus) was the largest of them all, with females standing almost 2m tall at the back (6'6") and able to reach their heads up to heights of around 3.6m (11'10"). It had a long neck, a relatively tiny head with a curved beak, and large powerful legs — and preserved hair-like body feathers show that it was reddish-brown in color.

It also had some of the most extreme sexual dimorphism seen in any bird species, with the males being significantly smaller than the females at only about 1.2m tall (3'11"). This seems to have been the result of scaling-up smaller differences in body size from their ancestors.

The adzebills were another odd group of big flightless birds whose ancestors also date back to sometime before the St Bathans deposits. They had large downward-curving beaks, short strong legs, and highly reduced wings that were smaller proportionally than those of the dodo.

They were less common than the moa, found only the drier forested parts of the lowlands, and based on isotope analysis of their bones they seem to have been predators hunting invertebrates, reptiles, and smaller birds.

When their remains were first discovered they were even thought to be a type of moa, but later studies (including recovered ancient DNA) have shown they were actually gruiformes, with their closest living relatives being either the South American trumpeters or the African flufftails.

The South Island adzebill (Aptornis defossor) was the slightly larger of the two species known from the Holocene, reaching sizes of about 0.8-1m tall (2'8"-3'3").

Origins of giant extinct New Zealand bird traced to Africa

Scientists have revealed the African origins of New Zealand's most mysterious giant flightless bird – the now extinct adzebill – showing that some of its closest living relatives are the pint-sized flufftails from Madagascar and Africa.

Led by the University of Adelaide, the research in the journal Diversity showed that among the closest living relatives of the New Zealand adzebills – which weighed up to 19 kilograms – are the tiny flufftails, which can weigh as little as 25 grams. The closeness of the relationship strongly suggests that the ancestors of the adzebills flew to New Zealand after it became physically isolated from other land.

This finding mirrors the close relationship between New Zealand's kiwi and the extinct Madagascan elephant birds, published by University of Adelaide researchers in 2014, hinting at an unappreciated biological connection between Madagascar and New Zealand.

Like the better-known moa, the two species of adzebill – the North Island adzebill and South Island adzebill –disappeared following the arrival of early Maori in New Zealand, who hunted them and cleared their forest habitats. Unlike the moa, adzebills were predators and not herbivores.

Some more watercolour doodles on the South Island Adzebill (Aptornis defossor), a large ground bird from New Zealand's South Island.

Adzebills are best known for their size, predatory habits and strong bill. These birds preyed on small animals, and may have used their beaks to dig out their prey, like weta or tuatara. And while they didn't match the Moa in size, at 80 cm tall and weighing 18 kg.

Date of extinction: ~1300

Adzebills are a family of flightless birds consisting 2 (probably 3) extinct species. Their closest relatives were the flufftails and the wood rails, all belonging to the order Gruiformes(a group consisting cranes, rails, coots, etc.) Adzebills were entirely flightless, having smaller wings than the dodo compared to their body size. They were 80 cm tall, and was the largest land predator in New Zealand. When their fossils were first discovered, they were thought to be some species of moa. They got their name after their adze-like beaks.

Adzebills were carnivorous, probably hunting and snatching any small animal they could find, for example lizards, bird chicks, eggs, insects or even bats. They probably had a similar breeding style of other gruids, like having ornamental feather and head fluffs, as well as more colourful feathers during mating season. They nested on the ground, with either both parents caring about the eggs and chicks (like most gruids) or mostly just the males (like kiwis).

Extinction: since they were rarer than other birds, adzebills faced bigger pressure from native maori hunters. The invasive rats and feral dogs also hunted their chicks, which lead to the decline of both the South island and the North island species. They went extinct somewhere in the 1300s.