Huia

The Huia was a species of songbird native to New Zealand’s North Island, which went extinct in the early 20th century. DNA sequencing has revealed that the Huia, together with its two close relatives, the Kokako (Callaeas) and the Saddleback (Philesturnus), all of which are New Zealand wattlebirds, belongs to an earlier branch of the songbird evolutionary tree. These species together form a distinct monophyletic group, separate from the Passerida and Core Corvoidea suborders. The ancestors of this monophyletic group may have migrated to New Zealand via “stepping-stone” islands, assisted by the westerly winds that formed when Australia and Antarctica separated in the late Eocene. ¹ It was previously thought that either the Huia or the Kokako might have been the earliest to diverge from this monophyletic group of New Zealand wattlebirds. More recent research has found that the common ancestor of the three New Zealand wattlebird species emerged around 6.8 million years ago during the late Miocene. The Kokako was the first to diverge, while the Huia and Saddleback formed a sister group, with their divergence occurring approximately 4.8 million years ago during the early Pliocene. ²

The Huia, measuring about 48 cm in length, was the largest species in the Callaeidae family. Its plumage was predominantly black with a slight dark blue sheen, except for a distinctive white band at the tips of the tail feathers. On either side of its face, near the tip of the beak, the Huia had prominent, round, orange wattles. Both sexes had white beaks with gray bases, but there was a significant difference in their shapes: the male’s beak was short and stout, while the female’s was long, slender, and had a pronounced downward curve.

The Huia primarily fed on insects that infested decaying wood, particularly the larvae of the Huhu beetle, which is native to New Zealand. Early explanations suggested that the significant difference in beak appearance between males and females likely facilitated cooperative foraging, with the male using his short, sturdy beak to chisel open the wood and the female using her long, slender beak to extract the insects. However, despite this phenomenon, the relationship between the sexes was not truly “cooperative.” ³ Instead, the evolution of different beak shapes was more about reducing intraspecific competition, as it allowed the sexes to exploit different food sources.⁴ They were often observed in pairs, exhibiting strong bonds, believed to have formed lifelong mating pairs. Occasionally, they were seen in small groups of four or more. ⁵ Nesting occurred in October, with eggs hatching by November, typically producing a clutch of 1 to 5 eggs. The Huia’s migratory behavior is unclear; while there is speculation that they bred in higher altitudes and wintered at lower elevations, the general consensus is that they were non-migratory. ⁶ Their recognizable call is a soft whistle, like their name. They are attracted to this sound, and Māori hunters take advantage of this by mimicking the sound to trap them.

The Huia was restricted to specific areas of New Zealand’s North Island, particularly in the southern mountains and forests. Fossil records indicate that they once had a broader distribution across the North Island, but their range was reduced due to the settlement of the Maori. The arrival of Europeans in the 19th century exacerbated the situation, leading to a dramatic population decline in the latter half of the century. This decline was primarily driven by extensive deforestation, as vast tracts of native forest, which provided the decaying wood that was essential to the Huia’s specialized diet, were cleared for agriculture. Additionally, commercial hunting targeted the Huia for its striking beak and tail feathers. Before European contact, the Maori also hunted Huia, using the birds to create valuable ornaments. However, a balance was maintained due to hunting restrictions and the bird’s sacred status in Maori culture, preventing the species from being driven to extinction. This balance was disrupted by the economic pressures introduced by European settlers, leading to the species’ eventual extinction.

The last confirmed sighting of the Huia occurred on December 28, 1907, near the Tararua Range, when W.W. Smith reported seeing two male birds and one female. However, there is some debate regarding the exact date of this sighting, with existing literature suggesting that it may have taken place sometime between 1905 and 1907. ⁷ In the 1920s, there were a series of unverified reports of Huia sightings, with sporadic, unconfirmed records even continuing as late as 1961. ⁸

Appearance #

• Male

  • The entire body is covered in black feathers with a deep blue sheen, except for the white tip of the tail feathers
  • The tail feathers, about 20 cm long, have a neat white band approximately 2.5 cm wide at the end
  • The short, thick beak is white with a bluish-gray tip, about 60 mm long, and there is a round orange wattle at the base of the beak
  • Legs and feet are bluish-gray

• Female

  • The plumage is same to that of the male, but the beak is long, slender, and curves downward, about 104 mm long
  • The female is slightly larger than the male, with a body length of about 48 cm, while the male’s body length is approximately 45 cm. ⁹

• Juvenile¹⁰

  • The feathers are duller in color compared to adults, with a rufous-yellow tip on the tail feathers
  • The wattle at the base of the beak starts as flesh-white
  • Male juveniles have pale-rufous and white tips on the feathers of the lower abdomen
  • Female juveniles have white-tipped undertail coverts

• Special

  • An albino Huia with entirely white plumage was once found near Wanganui. Another Huia was observed with brownish-black feathers marked with grey bands.
  • Some birds have a rufous tinge to the tailtip

Bill Dimorphism #

The exact reason for the evolution of extreme sexual dimorphism in the bills of the Huia remains uncertain. Earlier theories suggesting that male and female Huia cooperated in feeding through their differently shaped bills have been largely discredited. Other prominent theories propose that this evolutionary trait allowed them to diversify their diets, thereby reducing intraspecific competition.

Recent fossil studies have revealed that while the isotopic niches of male and female Huia differed, they also overlapped significantly, and both sexes occupied similar trophic positions. This suggests that while bill dimorphism led to partial foraging segregation between the sexes, there was still considerable overlap in their diets. Notably, the same study found that the female Huia had more stable and less variable trophic positions, indicating a more specialized foraging strategy, whereas the male’s diet was relatively broader. The female Huia was the only bird in its ecological environment specialized in probing wood for insects, a behavior that might have evolved as an adaptation to exploit a broader foraging niche. When comparing the Huia to its closest evolutionary relative, the Saddleback, which has short, stout bills in both sexes, it can be inferred that the Huia’s bill dimorphism evolved as the female’s bill adapted to expand its foraging range, while the male retained more ancestral traits. ¹¹ The divergence between the Huia and Saddleback occurred around 4.8 million years ago.

This trend towards specialized foraging might have also contributed to the Huia’s extinction in modern times. The female’s long bill, suited for deep wood probing, made them highly dependent on native forests as their habitat. As the original forest cover on New Zealand’s North Island decreased, the Huia, particularly the females, were heavily impacted.

Life History #

Breeding and Rearing #

The Huia raised only one brood per breeding season, with clutches typically containing 1 to 5 eggs, though the most common description is of 4 eggs¹². They laid eggs in October, with chicks hatching in November. Nesting sites were dispersed, and males were territorial, often remaining in their nesting territory for life. A pair in captivity was observed during the breeding season engaging in courtship behavior, which included hopping from branch to branch, occasionally fanning their tails, and meeting to caress each other with their bills while emitting low twittering contact calls¹³.

Nesting sites were flexible, with some nests built on or near the ground, usually at the base of large trees, while others were located higher up, such as in dead trees, tree hollows, depressions at the top of truncated trees, or on branches. These nests were sometimes covered by overhanging foliage, epiphytic growth, or vines. The nests were large and saucer-shaped, with a deep central cup that could be up to 7 cm deep¹⁴. The internal diameter of the cup was approximately 18 cm, and the external diameter of the nest was around 35 cm. The thick walls of the nest were made of dry grass, leaves, and withered stems of herbaceous plants. Different parts of the nest were observed to be constructed with varying materials, indicating a high level of craftsmanship. The base of the nest was primarily composed of leaves and some dead sticks, the walls were formed by interwoven sticks and leaves, and the inner cup was lined with softer, finer materials such as grass, leaves, stems, or twigs¹⁵.

The female was primarily responsible for incubation, though the male also assisted, as indicated by the presence of smaller brood patches on males during the breeding season. The eggs were stone-colored with irregular purplish-gray spots. No eggshell fragments were found in the nest after hatching, suggesting that the parents likely removed them.¹⁶ After hatching, the chicks were unable to feed themselves and were cared for in the nest by both parents ¹⁷ for at least three months, until their plumage resembled that of their parents.

Diet #

The primary food source for the Huia was the larvae of the New Zealand endemic Huhu beetle (Prionoplus reticularis), but they also consumed various seeds, fruits, and small insects. They were often observed foraging in decaying wood, with small groups of four to five birds seen stripping moss and epiphytic ferns from tree branches and trunks in search of insects. ¹⁸

The diet of the Huia differed slightly between the sexes due to the distinct characteristics of their beaks. Males, with their strong cranial musculature and robust beaks, were capable of chiseling and breaking apart rotten wood to access the insects within. In contrast, the long, slender beak of the female was well-suited for probing deeper into crevices to capture prey. Although pairs of Huia were often observed “cooperating” in foraging, it was generally the case that they did not share food; a female would not give her catch to the male, and vice versa.

The recorded diet of the Huia includes the following¹⁹:

• Plants: Fruits and vegetables

  • Gymnosperms: Podocarpaceae family: Fruits of Kahikatea (correctly named Dacrycarpus dacrydioides).
  • Dicotyledons:
    • Cunoniaceae family: Seeds of the Tawhero tree (Weinmannia silvicola).
    • Elaeocarpaceae family:
      • Fruits and seeds of Hinau (Elaeocarpus dentatus).
      • Fruits of Pokaka (Elaeocarpus hookerianus).
    • Icacinaceae family: Seeds of Kaikomako (Pennantia corymbosa).
    • Monimiaceae family: Fruits of Pigeonwood (Hedycarya arborea).
    • Rubiaceae family: Fruits of Shining Karamu (Coprosma lucida).

• Animals:

  • Spiders
  • Coleoptera: Larvae of the Huhu beetle (Prionoplus reticularis).
  • Diptera (flies and mosquitoes)
  • Lepidoptera (moths): Larvae
  • Mantodea (mantises)
  • Orthoptera: Auckland tree weta (Hemideina thoracica).

In captivity, the Huia was fed a diet that included cooked potatoes, boiled rice, raw minced meat, and a mixture primarily composed of boiled eggs, fresh meat, and earthworms.

Voice #

The Huia often vocalized at dawn, typically being the first bird to begin the forest’s dawn chorus.²⁰ They would become cheerful and produce melodious songs before rain. Their calls mainly consisted of various whistle-like sounds, similar to flute tones, which were soft and melodious. Although their voices were gentle, they could still be heard from up to 400 meters away. When calling, the bird’s head and neck would stretch upward. There are accounts suggesting that the calls of males and females differed, but no further specifics were provided. Juveniles were likely noisier than adults.²¹

The recorded vocalizations of the Huia include the following²²:

• Whistle contact calls between adults: These were the most common sounds. They were soft, deep, and rich in tone, consisting of several short, quick twittering whistle notes. This sound was usually produced during flight, though it was also heard occasionally during foraging. The low-pitched calls during courtship might also belong to this category.

• Distress calls: Produced when the birds were excited or hungry. These were shrill, high-pitched whistles repeated multiple times, sounding like “uia-uia-uia” or “where-are-you,” from which the Huia’s name is derived.

• Scream: A single long screech followed by two short ones, recorded only once in the morning. ²³

• Cry: A soft, musical, whimpering note, almost indistinguishable from the whining of young puppies. The plaintive cry of juveniles was reportedly very pleasant to the ear.

• Chuckle: A low chuckling sound.

The Huia was often attracted to whistled imitations of its calls, sometimes being lured from as far as 100 meters away. Humans exploited this characteristic to hunt them. Occasionally, the birds would respond to human imitations with low chirping note, low tremulous whistle or whimper. Juveniles responded even more feebly to these imitations.²⁴

Habitat and Distribution #

The Huia primarily inhabited forests with dense undergrowth in mountainous and lowland areas, such as those commonly found on New Zealand’s North Island, where podocarp conifers and hardwood broadleaf trees coexist. They were also observed in Nothofagus forests. ²⁵The Huia was never observed in forests that had been burned or in land cleared for agriculture.²⁶

The Huia was only found on the North Island of New Zealand. There were some unconfirmed sightings on the South Island, but no subfossil records have been found. Historically, they were distributed across much of the North Island, but after the arrival of the Maori, their range contracted to a portion of the southern North Island. By the time Europeans arrived in New Zealand in the mid-19th century, the confirmed distribution was as follows²⁷:

• Ruahine, Tararua, and Rimutaka Ranges, extending south from Mataroa and Taihape to the ranges on either side of Wellington Harbour and the hills around Palliser Bay and Lake Wairarapa

  • In 1892, only one Huia was sighted during an expedition in the ranges behind Waikanae and the Hutt River Valley, although the species had been common in this area in the mid-1880s.
  • Around 1898, they were still relatively common in the Utiku area near Taihape.
  • Between 1889 and 1893, the population in the Tararua Range declined and became rare.
  • They were still relatively common around the Akatarawa River near the Rimutaka Range before 1900.
  • In 1905, a flock of 100-150 birds was recorded at the summit of the Akatarawa-Waikanae Track near the Rimutaka Range.

• Lowlands adjacent to the above ranges, such as from the northern Hutt River Valley to the western areas near Shannon, and from Riversdale Beach inland north through the Puketoi Range and Dannevirke, extending to Patanga in the east

  • Survived in the Puketoi Range until the 1880s, after which the population gradually declined.
  • In 1883, many specimens were collected in the Pahiatua-Dannevirke area, but by the 1890s, the population there had become extinct.
  • In 1895, they were common around Akitio on the eastern coast of the North Island, but by around 1901, they had almost disappeared.
  • In the early 1900s, they were still relatively common in the lowlands between Hawkes Bay and Wairarapa.

• Forested areas along the upper and middle reaches of major rivers, such as the Rangitikei River and its tributaries

  • In 1906, they were still relatively common in the upper reaches of the Rangitikei River.

• More northern areas with scattered records, including the middle reaches of the Wanganui River, extending north through Tongariro National Park to the southern part of Lake Taupo, and then east to the Huiarau Range (which literally means ‘a hundred Huias’)

• Isolated records, including near Mahoenui in the west and in the southern Raukumara Range in the east