page_title: Haast's eagle
section_title: Description
hierarchical_section_title: Haast's eagle / Description
caption_attribution_description: Comparison of the huge claws of Harpagornis moorei with those of its close relative the Hieraaetus morphnoides, the “little” eagle. The massive claws of H. moorei could pierce and crush bone up to 6 mm thick under 50 mm of skin and flesh.
context_page_description: The Haast's eagle is an extinct species of eagle that once lived in the South Island of New Zealand, commonly accepted to be the pouakai of Maori legend. The species was the largest eagle known to have existed, with an estimated weight of 15 kilograms nearly double that of the Harpy eagle at 9 kilograms. Its massive size is explained as an evolutionary response to the size of its prey, the flightless moa, the largest of which could weigh 230 kg. Haast's eagle became extinct around 1400, after the moa were hunted to extinction by the first Māori.
context_section_description: Haast's eagles were one of the largest known true raptors. In length and weight, Haast's eagle was even larger than the largest living vultures. Another giant eagle from the fossil record, Amplibuteo woodwardi, is more recently and scantly-described but rivaled the Haast's in at least the aspect of total length. Female eagles were significantly larger than males. Most estimates place the female Haast eagles in the range of 10–15 kg (22–33 lb) and males around 9–12 kg (20–26 lb).
  A comparison with living eagles of the Australasian region resulted in estimated masses in Haast's eagles of 11.5 kg (25 lb) for males and 14 kg (31 lb) for females. One source estimates that the largest females could have scaled more than 16.5 kg (36 lb) in mass. The largest extant eagles, none of which are verified to exceed 9 kg (20 lb) in a wild state, are about forty percent smaller in body size than Haast's eagles.
  They had a relatively short wingspan for their size. It is estimated that the grown female typically spanned up to 2.6 m (8.5 ft), possibly up to 3 m (9.8 ft) in a few cases. This wingspan is broadly similar to the larger range of female size in some extant eagles: the wedge-tailed eagle (Aquila audax), golden eagle (A. chrysaetos), martial eagle (Polemaetus bellicosus), white-tailed eagle (Haliaeetus albicilla) and Steller's sea eagle (Haliaeetus pelagicus) are all known to exceed 2.5 m in wingspan. Several of the largest extant Old World vultures, if not in mean mass or other linear measurements, probably exceed Haast's eagle in average wingspan as well.
  Short wings may have aided Haast's eagles when hunting in the dense scrubland and forests of New Zealand. Haast's eagle has sometimes been portrayed incorrectly as having evolved toward flightlessness, but this is not so. Rather it represents a departure from the mode of its ancestors' soaring flight, toward higher wing loading and the species probably had very broad wings.
  Some wing and leg remains of Haast's eagles permit direct comparison with living eagles. The harpy eagle (Harpia harpyja), the Philippine eagle (Pithecophaga jefferyi), and the Steller's sea eagle (Haliaeetus pelagicus) are the largest and most powerful living eagles, and the first two also have a similarly reduced relative wing-length as an adaptation to forest-dwelling. A lower mandible from the Haast's eagle measured 11.4 cm (4.5 in) and the tarsus in several Haast's eagle fossils has been measured from 22.7 to 24.9 cm (8.9 to 9.8 in). In comparison, the largest beaks of eagles today (from the Philippine and the Steller's sea eagle) reach a little more than 7 cm (2.8 in); and the longest tarsal measurements (from the Philippine and the Papuan eagle) top out around 14 cm (5.5 in).
  The talons of the Haast's eagle were similar in length to those of the harpy eagle, with a front-left talon length of 4.9 to 6.15 cm (1.93 to 2.42 in) and a hallux-claw of possibly up to 11 cm (4.3 in). The Philippine eagle might be a particularly appropriate living species to compare with the Haast's eagle, because it too evolved in an insular environment from smaller ancestors (apparently basal snake eagles) to island gigantism in the absence of large carnivorous mammals and other competing predators.
  The strong legs and massive flight muscles of these eagles would have enabled the birds to take off with a jumping start from the ground, despite their great weight. The tail was almost certainly long, in excess of 50 cm (20 in) in female specimens, and very broad. This characteristic would compensate for the reduction in wing area by providing additional lift. Total length is estimated to have been up to 1.4 m (4 ft 7 in) in females, with a standing height of approximately 90 cm (2 ft 11 in) tall or perhaps slightly greater.
caption: A comparative morphology of Haast's eagle with its closest living relative, the little eagle.
exif: {}