Pygmy eagle

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Pygmy eagle
Hieraaetus weiskei 3151415.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Hieraaetus
Species:
H. weiskei
Binomial name
Hieraaetus weiskei
(Reichenow, 1900)
Hieraaetus morphnoides ssp weiskei distribution map.png
Synonyms

Hieraaetus morphnoides weiskei

The pygmy eagle or New Guinea hawk-eagle [2] (Hieraaetus weiskei) is a bird of prey found in New Guinea. Its natural habitats are primarily subtropical or tropical moist lowland forest and subtropical or tropical moist montane forest. It is the one of the smallest species of eagle.

Contents

Taxonomy

The pygmy eagle was described by German naturalist Anton Reichenow as Eutolmaetus weiskei in 1900. It was subsequently considered a subspecies of the little eagle or a distinct species. Gjershaug and colleagues analysed it genetically and found it distinct enough to warrant species status. [2] [3] The International Ornithologists' Union (IOC) subsequently recognised it as a distinct species. [4] "Pygmy eagle" has been designated the official name by the IOC. [4]

Description

Size

The pygmy eagle is one of the world's smallest-known species of eagle and smallest living member of the Aquilinae subfamily, [2] only rivaled by the Great Nicobar serpent eagle in diminutive size by all modern species referred to as eagles. Pygmy eagle measures 38 to 48 cm (15 to 19 in) in length. The wingspan measures 112 to 126 cm (44 to 50 in). The female eagle is slightly larger than the male. One male pygmy eagle was found to weigh 483 g (1.065 lb). [5] [6] One study estimated the body mass of males of the species to fall around 406 g (0.895 lb) while that of females to fall around 555 g (1.224 lb). [7]

Identification

The pygmy eagle shares many characteristics with its counterpart the little eagle. The most notable differences are color. The pygmy eagle has darker more pronounced streaks on the nape, crown and ventral. The bird also shares characteristics with the booted eagle, both eagles have a unique underwing pattern. The plumage of the pygmy eagle can vary depending on the morph, light or dark. The dark morph is very similar to the dark morph of the little eagle, while the light morph shows the most differences that occur in the dark streaking. The dark morph seems to be rarer as 10 out of 11 field sightings have been the light morph. The feet of the eagle are described as grey or dull yellow. [8]

Voice

The voice of the pygmy eagle has been described as a "sip sip yeeee" during flights. The call can also be compared to the little eagle and booted eagle. The bird has also been observed giving a weaker single tone squeal. [8]

Distribution and habitat

The pygmy eagle primarily resides in lowland forests and forest edges in New Guinea. They enjoy nesting in closed forestry but have also been seen in open habitat and forest edges. The bird seems to be sparsely distributed throughout the hilly forests of New Guinea; however much of the forests of New Guinea are inaccessible so the eagle may be more abundant than it seems. One of the densely forested parts of New Guinea is Vogelkop or Bird's Head Peninsula. The pygmy eagle has been observed nineteen times in the Vogelkop over three years. It has also been observed on the island Buru and in the northern Moluccas. [8]

Food

Pygmy eagles have been seen soaring and diving on prey in forest canopies. The raptor is capable of very swift dives and attacks other avians such as the brown cuckoo-dove and mountain fruit-dove. Usually, the raptor low soars over the canopy scanning for prey and then dives on other birds in the canopy. [8]

Related Research Articles

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<span class="mw-page-title-main">Accipitridae</span> Family of birds of prey

The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds of prey with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-sized mammals, with a number feeding on carrion and a few feeding on fruit. The Accipitridae have a cosmopolitan distribution, being found on all the world's continents and a number of oceanic island groups. Some species are migratory. The family contains 255 species which are divided into 70 genera.

<span class="mw-page-title-main">Golden eagle</span> Species of eagle

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<span class="mw-page-title-main">Booted eagle</span> Species of bird

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<span class="mw-page-title-main">African hawk-eagle</span> Species of bird

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<span class="mw-page-title-main">Wahlberg's eagle</span> Species of bird

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<span class="mw-page-title-main">Mountain hawk-eagle</span> Species of bird

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<span class="mw-page-title-main">Rufous-bellied eagle</span> Species of bird

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<i>Aquila</i> (bird) Genus of birds

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<span class="mw-page-title-main">Cassin's hawk-eagle</span> Species of bird

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<span class="mw-page-title-main">Aquilinae</span> Subfamily of birds

The Aquilinae are a subfamily of eagles of the family Accipitridae. The general common name used for members of this subfamily is "booted eagle", although this is also the common name of a member of the subfamily. At one point, this subfamily was considered inclusive with the Buteoninae based probably on some shared morphological characteristics. However, research on the DNA of the booted eagles has shown that they are a monophyletic group that probably have had millions of years of separation from other extant forms of accipitrid.

Booted eagles are eagles that have fully feathered tarsi. That is, their legs are covered with feathers down to the feet. Most other accipitrids have bare lower legs, scaled rather than feathered.

References

  1. BirdLife International (2016). "Hieraaetus weiskei". IUCN Red List of Threatened Species . 2016: e.T22734094A95074293. doi: 10.2305/IUCN.UK.2016-3.RLTS.T22734094A95074293.en . Retrieved 15 November 2021.
  2. 1 2 3 Gjershaug, Jan Ove; Lerner, Heather R.L.; Diserud, Ola H. (2009). "Taxonomy and distribution of the Pygmy Eagle Aquila (Hieraaetus) weiskei (Accipitriformes: Accipitridae)" (PDF). Zootaxa. 2326: 24–38. doi:10.11646/zootaxa.2326.1.2.
  3. "Hieraaetus weiskei". Avibase.
  4. 1 2 Gill, Frank; Donsker, David, eds. (2017). "New World vultures, Secretarybird, kites, hawks, eagles". World Bird List Version 8.1. International Ornithologists' Union. Retrieved 18 April 2018.
  5. "New Guinea Hawk Eagle – Aquila weiskei". The Eagle Directory. Retrieved 16 April 2018.
  6. del Hoyo, J., N. Collar, and J. S. Marks (2020). Pygmy Eagle (Hieraaetus weiskei), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA.
  7. Parry, S. J. (2001). The booted eagles (Aves: Accipitridae): perspectives in evolutionary biology. University of London, University College London (United Kingdom).
  8. 1 2 3 4 Debus, Stephen (August 2017). Australian Eagles and Eagle Like Birds (1 ed.). CSIRO Publishing. ISBN   9781486306930 . Retrieved 16 April 2018.