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Selinayu1215/sandbox
Temporal range: Late Holocene
Pachyornis australis bones in Ngarua Caves
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Infraclass: Palaeognathae
Order: †Dinornithiformes
Family: †Emeidae
Genus: †Pachyornis
Species:
†P. australis
Binomial name
†Pachyornis australis
(Oliver, 1949)[1][2]
Synonyms
List
  • Pachyornis elephantopus Cracraft 1976 non (Owen 1856) Lydekker 1891
  • Mesopteryx sp. β Parker 1895

The crested moa (Pachyornis australis) is an extinct species of moa. It is one of the 9 known species of moa to have existed.[3]

Moa are grouped together with emus, ostriches, kiwi, cassowaries, rheas, and tinamous in the clade Palaeognathae. Some of the species of this group are flightless and lacks a keel on their sternum.[4] The name crested moa is due to pits being found in their skulls, suggesting they had crests of long feathers.[3][5] These cranial pits are also found occasionally in Dinornis, Anomalopteryx, and other Pachyornis species.[6]

Taxonomy and Classification

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The crested moa belongs to the order Dinornithiformes, a group of large, flightless birds that were endemic to New Zealand. Within this order, it is classified under the family Emeidae, which includes the genus Pachyornis, consisting of three recognized species: P. elephantopus (heavy-footed moa), P. geranoides (slender moa), and P. australis (crested moa). The species was first described by Walter Reginald Brook Oliver in 1949, based on fossil evidence recovered from South Island cave deposits.

The crested moa is distinguished from its relatives by unique cranial pits, which suggest the presence of feather crests. These features are shared with some species of Dinornis and Anomalopteryx, but they are most developed in P. australis, giving the species its common name[5]. Although Pachyornis elephantopus and Pachyornis australis had similar skeletal structures, particularly in their robust limb bones, their geographical distribution and ecological adaptations set them apart[7].

Description

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The crested moa weighed around 75 kg (165 lb). The crested moa was smaller than the heavy-footed moa (Pachyornis elephantopus) and their bones are sometimes mistaken for those of P. elephantopus due to their similar structure.[7][8]

Almost nothing is known about the feather pits on the crested moa's skull. It is likely the feathers were used in courtship rituals or to challenge rivals, but no feathers have been found so their color or size can only be speculated at.[3]

Behavior and Life Cycle

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Like all moa species, the crested moa was herbivorous and highly adapted to a terrestrial lifestyle, given New Zealand's lack of native terrestrial mammals[9]. Its large, robust beak suggests it consumed fibrous plant material, including leaves, twigs, and shrubbery, similar to the diet of other Pachyornis species. The presence of gizzard stones found in association with its remains indicates that, like other moa, it relied on gastroliths to break down tough plant material[3].

Given its subalpine habitat, the crested moa may have had seasonal migration patterns, moving to lower altitudes in winter when food sources in the highlands became scarce[8]. Though there is no direct fossil evidence of nesting behavior, its relatives in the Pachyornis genus likely laid large eggs in simple ground nests, similar to other moa species[10]. Parental care strategies remain speculative, but evidence from closely related moa species suggests that males may have been the primary caretakers of eggs and hatchlings.

Distribution and habitat

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The crested moa was endemic to the South Island of New Zealand, where it occupied the high altitude sub-alpine forests in the North West, particularly in the Nelson area.[3][8][10] Crested moa remains have been found in the Honeycomb Hills Cave and other caves in the vicinity.[3] It was the ecological equivalent of the heavy-footed moa in the subalpine zone. While their remains have occasionally been found together, the heavy-footed moa generally preferred warmer and drier lowland areas.[7][8][10] However, it is likely the crested moa would have migrated from the high country to these more hospitable areas in winter.[3]

Ecology and diet

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As with all moa species, the crested moa filled the role of large herbivores in New Zealand, where there are no native terrestrial mammals (excluding bats).[8][9] The robust beak with a pointed tip, sturdy jaws, together with large numbers of gizzard stones suggests the diet of Pachyornis was high in fibrous plant material such as branches of trees and shrubs.[5] The only real threat of predation came from the Haast's eagle (Hieraaetus moorei).[9]

Predation

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Before human arrival, the crested moa faced few natural predators, with the Haast’s eagle being its only known major threat. The Haast’s eagle, the largest eagle species ever recorded, was capable of preying on even the largest moa species, using its powerful talons to strike at the neck and head[9]. The crested moa’s subalpine habitat may have offered some protection, as the Haast’s eagle was more commonly associated with lowland forests, but subfossil evidence suggests these eagles had a wide hunting range[10].

Natural Threats

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Environmental pressures such as climate shifts during the Late Pleistocene and early Holocene may have influenced crested moa populations. Changes in temperature and vegetation distribution led to shifts in suitable habitats, forcing these moa to migrate seasonally[8]. However, unlike some moa species that occupied widespread lowland forests, the crested moa had a more restricted range, which may have made them more vulnerable to habitat loss.

Human Interaction and Cultural Significance

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Unlike many other moa species that were extensively hunted by the early Māori, there is no direct evidence that crested moa were commonly targeted by humans[3]. Due to their isolated, high-altitude habitats, they were likely difficult to access, making them less of a priority for early Polynesian settlers who relied on moa as a food source. Archaeological sites containing moa remains, such as those in Canterbury and Otago, rarely include crested moa bones, further supporting the idea that they were not a primary target for hunting[5]

However, indirect human impact, such as habitat destruction and the introduction of mammalian predators, may have played a role in their decline. The arrival of rats and dogs, brought by Polynesian settlers, could have disturbed nesting sites or competed for food resources[7]. Given that the crested moa survived over a century after human settlement—longer than most other moa species—it suggests they may have persisted in remote pockets of subalpine forests until their eventual extinction[8].

There is no recorded Māori mythology directly referencing the crested moa, but as with all moa, they were likely recognized as part of the sacred landscape and traditional knowledge systems[10]. The extinction of the crested moa marked the loss of one of New Zealand’s last megafaunal herbivores, permanently altering the country’s ecological balance.

Fossil Discoveries and Research

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Fossil evidence of the crested moa has been primarily recovered from limestone caves and subalpine regions of the South Island, New Zealand, with notable discoveries in the Honeycomb Hills Cave system and Bulmer Cavern[7]. These sites, rich in well-preserved subfossil remains, have provided key insights into the physical structure, habitat preferences, and extinction timeline of this species.

Initially, the crested moa was believed to have gone extinct at the Pleistocene-Holocene transition, approximately 10,000 years ago, due to climate-driven habitat changes[11]. However, in 2012, radiocarbon dating of a fossil specimen from Bulmer Cavern revised this estimate, confirming that the species survived until at least 1396–1442 AD, over a century after human settlement in New Zealand[8]. This finding suggests that the crested moa was one of the last surviving moa species, possibly due to its remote, high-altitude habitat, which shielded it from early human hunting pressures.

Additionally, some Pachyornis australis fossils show evidence of cranial feather pits, leading paleontologists to hypothesize that the species may have had a distinctive feather crest. However, no preserved feathers have been found, leaving the function, color, and size of the crest unknown[5]. Research on bone morphology has also shown similarities between P. australis and P. elephantopus, occasionally leading to misidentifications of their remains[10]. Advances in ancient DNA analysis and paleogenomics may offer new insights into the evolutionary history of the crested moa, shedding light on its genetic diversity and adaptation to subalpine environments.

Extinction

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Until recently it was thought that the crested moa became extinct at the Pleistocene-Holocene transition roughly 10,000 years ago (10,000 years BP) during a period of significant climatic upheaval.[8][11] In 2012 however radiocarbon dating of crested moa remains from Bulmer Cavern showed that the specimen died between 1396 and 1442 AD, over 100 years after humans first settled on the Island.[7][8] During the climatic changes before the settlers arrived, the crested moa followed the changes in elevation of their sub-alpine habitats with little change in their population size. Despite their relatively low numbers and limited habitat range, their extinction came later than all of the other moa species. Given that there is no evidence that crested moa were ever hunted by humans[5] (unlike every other species of moa), it seems likely that their populations were too isolated and remote to have been accessed by humans.[3][7][8] Instead, it is probable that the crested moa were wiped out by introduced mammals.[3]

Footnotes

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  1. ^ Oliver 1949, pp. 70–74
  2. ^ Checklist Committee Ornithological Society of New Zealand (2010). "Checklist-of-Birds of New Zealand, Norfolk and Macquarie Islands and the Ross Dependency Antarctica" (PDF). Te Papa Press. Retrieved 4 January 2016.
  3. ^ a b c d e f g h i j Berentson, Quinn (2012). Moa: the life and death of New Zealand's legendary bird. Craig Potton Publishing. ISBN 9781877517846.
  4. ^ Davies 2003, pp. 95–98
  5. ^ a b c d e f Tennyson, Alan J. D. (2006). Extinct birds of New Zealand. Paul Martinson. Wellington, N.Z.: Te Papa Press. p. 26. ISBN 978-0-909010-21-8. OCLC 80016906.
  6. ^ Olliver 2005
  7. ^ a b c d e f g Rawlence & Cooper 2012
  8. ^ a b c d e f g h i j k Rawlence et al. 2012
  9. ^ a b c d Cooper et al. 1993
  10. ^ a b c d e f Worthy 1990
  11. ^ a b Williams et al. 2005

References

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  • Worthy, T. H. (1990). "An analysis of the distribution and relative abundance of moa species (Aves: Dinornithiformes)". New Zealand Journal of Zoology. 17 (2): 213–241. doi:10.1080/03014223.1990.10422598.
  • Tennyson, Alan J. D. Extinct Birds of New Zealand. Paul Martinson, Te Papa Press, 2006
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