Range
There are conflicting reports about how widespread Huia were in New Zealand. Some reports say that they were only found in the mountainous regions of the North Island (Te Ika-a-Māui), while there are also reports of Huia being sited in the Marlborough and Nelson regions of the South Island (Te Wai Pounamu).
Either way, it is known that their range reduced upon the arrival of the first humans (Māori), and dramatically upon the formal European settlement of New Zealand in 1840. The last official siting of Huia in the wild was in 1907, in the Tararua Ranges.
Habitat
Huia lived in tall forests with dense understory (the level immediately below the canopy).
The main tree species in these forests were Mataī, Rimu, Kahikatea, Northern Rātā, Maire, Hinau, Totara, Rewarewa, Mahoe, and Taraire. Many of these trees would have provided both shelter and food for Huia. Huhu grubs, Weta and spiders would be found in the decaying wood of trees. The forest was also a home to many insect varieties. Additionally, some of these trees produce berries, another food source for many bird species including Huia.
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| Mataī |
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| Rimu |
Unfortunately for the forest-dwellers, the wood from these trees made for excellent furniture and housing. The forests were also very dense, so needed to be cleared to make the land available for human use.
Huia were never found in land cleared for farming or burnt forest. The deforestation of New Zealand's forests by both Māori and European settlers played a large part in Huia becoming endangered, then extinct.
Environment
The mountainous regions of New Zealand's North Island are described as temperate, but can be subject to snow and strong winds. Temperatures seldom exceed 30°C and rainfall is relatively uniform throughout the year (although the winter months are cooler and wetter). Water availability is rarely a limiting factor in these regions of New Zealand.
The size of the trees found in New Zealand forests protect the forest floor and understory from many of the more adverse weather conditions. However, they also limit the availability of light for many plants on the forest floor; plants below the canopy tend to have large leaves to make the most f the light that does filter through. The strong winds would cause branches to break, giving a food source for decomposers in the habitat.
Relationships
The New Zealand forest relies upon frugivorous birds such as Huia for seed dispersal. Huia would only be able to eat fruits smaller than 1cm in diameter, so only involved in the dispersal of Hinau, Kahakitea and some indigenous Coprosma species. It would have been in competition with other birds, particularly the NZ Wood Pigeon (Kereru). Decline in numbers of these birds (along with deforestation by humans) contributed to the decline of New Zealand forest. Huia were possibly also in competition with the NZ bat (pekapeka), which eats the berries of many indigenous plants.
Huia would also have competed with many other bird species for insects, spiders and larvae found in decomposing logs. Kiwi were a very successful forager, but were nocturnal which would limit the direct competition between these species.
The extinction of Huia also led to the extinction of a parasitic louse, Rallicola extinctus, as it lost its host. It did not have an alternate host.
Huia had no natural predators, but the arrival of the Māori saw the introduction of the Polynesian rat (kiore) which would predate upon Huia chicks. Dogs (kurī) were also introduced by the Māori and it is likely they predated upon adult Huia. Europeans brought many more predators, including cats and stoats.
While the Māori did hunt Huia for their ornate feathers and their beaks, there are varied reports about whether they made good eating or not. When the Māori noticed Huia numbers declining, they would declare them sacred (tapu), banning the hunting/killing of them. Māori chiefs would ask European settlers to not hunt Huia in these times. Sadly, early European settlers did not have the same conservation focus as the Māori.
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