Agriornis, and Ailuroedus A-Z of bird genera (13}

Great Shrike Tyrant

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Introduction

In this series A-Z of bird genera,we review the species that occur within certain genera. These species are diverse both in size form and distribution occurring all over the globe. Descriptions and images along with conservation status will be included. Here in this article we review the species that occur in three genera and we commence with the genus Agriornis.

The genus Agriornis

The genus Agriornis consists of the Shrike Tyrants of which there are five species that occur in open habitats in western and southern South America,usually at high elevations. They are large and heavy billed compared with other tyrant fly-catchers species and includes the largest member-The Great Shrike Tyrant. They belong to the family Tyrannidae within the order of birds known as the Passeriformes {perching birds}. Despite their name they are not related to the true Shrikes and are more akin in appearance to the unrelated Thrushes. Wecommence with the Black billed Shrike Tyrant.

Illustration of Black billed Shrike Tyrant

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Black-billed Shrike Tyrant

Agriornis montanus, is the Black-billed shrike tyrant. It is found in Argentina,Bolivia,Chile, Ecuador and Peru,and it has been recorded as a vagrant to the Falkland Islands.It is about ten inches long and it inhabits the sub-tropical or tropical high altitude shrub-land or high altitude grassland and pastures. It is the more widespread and adaptable of the Shrike Tyrants. It is sometimes encountered in Highland towns and villages, often utilizing television aerials on which to perch and declare their presence by singing.

It is a relatively slim bird with extensive white on the tail,but the amount can be vary variable. A distinct feature is the long and thin bill for a member of this genus,entirely black on the mandibles. It is also very vocal with loud whistle like s. They are usually observed as solitary birds or in pairs. There are five sub-species recognized and occur in a widespread geographical distribution.

Illustration of Agriornis albicaudata sub species pollen

Joseph Smit  Catalogue of the Birds in the British Museum Volume 14.
Joseph Smit Catalogue of the Birds in the British Museum Volume 14. | Source

The White -tailed Shrike Tyrant

Agriornis albicauda is the White-tailed Shrike Tyrant,and is found in Argentina, Bolivia, Chile, Ecuador and Peru. This species is ten to eleven inches long,making it a very large fly-catcher. Only the Great Shrike Tyrant is larger in size {See below}. . Even though this species has a broad range it is rare and hard to come by and they only occur in low densities wherever they are found. They are very similar to the previous species with a bit of white on the tail, however, this species has a thicker bill and there is a yellowish or horn -coloured base to the mandible. It is also a larger and more pot-bellied and stockier than the Black -billed Shrike tyrant.

To confuse identification more, there are named sub-species,one in Ecuador and the other occurs in north central Peru. According to the IUCN, it is classed as being a Vulnerable species.

The Great Shrike Tyrant

Agriornis lividus, {header image}, is the Great Shrike Tyrant, which is found in Argentina and Chile,and is the largest member of the genus being from ten and three quarters up to twelve inches long. This species also occurs in low densities throughout its southerly range. Although widespread in Chile it is elusive and far from vocal,and very few recordings of its voice are available. It has a thick bill with a large terminal hook.

For the size of this bird it takes surprisingly large prey which includes Lizards. Little is known about its nesting habits In central Chile , the northern parts of its range, it inhabits slopes, coastal dunes, forest edge and rocky outcrops. It is not a bird of current conservation concern.

Illustration of the Grey bellied Shrike Tyrant

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The Grey-Bellied Shrike Tyrant

Agriornis micropeteris,is the Grey-Bellied Shrike Tyrant, a bird found in Argentina,Bolivia, Chile, Paraguay,Peru and Uruguay. It inhabits the sub-tropical and tropical dry shrub land and grassland. As with all members of this genus it is little known. Unlike the Black-Billed Shrike Tyrant this species has a long, dark tail. The under parts are a dullish grey brown,which distinguishes from the larger and distinctive cinnamon bellied Great Shrike Tyrant.

It seems this species has to major populations one in the Altiplano of Peru,Bolivia, Argentina and Chile, which tend to be resident. The other population occurs on the Patagonian Steppe, which are migratory. There are no current conservation concerns.

Lesser Shrike Tyrant

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Lesser Shrike Tyrant

The final member of this genus is the Lesser Shrike Tyrant. Agrigornis murinus and was included in the genus Xolmis. The flight display of this species in unlike any other Shrike Tyrant,and there is still a dispute among ornithologists as to whether it belongs to this genus at all. It is very similar in fact to the Spot-billed ground Tyrant in the genus Muscisaxicola.

It is a bird of shrubby Patagonian Steppe, and migrates north during the non-breeding season,as far north as southern Bolivia. The general plumage is greyish above,paler below with some buff on the flanks, and a distinctive white edging on the wings and sides of the tail. It also lacks the larger bill of the other Shrike tyrants. There are no current conservation concerns.

White-eared Catbird.

Taken at Denver Zoo Colorado. USA
Taken at Denver Zoo Colorado. USA | Source

White-eared catbird

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The Genus Ailuroedus

The genus Ailuroedus belongs to the family Ptilonorhynchidae {Bower birds},within the order Passeriformes {perching birds},and contains three species. The genus name derives from Greek and indicates 'Cat voiced' and they are collectively known as Catbirds.

We commence with the White-eared Catbird, Ailuroedus buccoides, a bird of Indonesia and Papua New Guinea,where they inhabit forests and occasionally forest edge up to an altitude of between eight hundred and twelve hundred meters.They have a brown crown with tints of green,mostly whitish ear-coverts,side of the lower head and throat with some black spotting. The upper neck is a buff colour with black feathers that form a broad spotted collar.

The upper parts area rich green as are the upper wings and upper tail. The flight feathers are a brownish olive colour with broader cream coloured trailing edges.The under parts are a light pale cinnamon with large black spots. The under tail is dark brown. The eye is deep red the bill whitish. The female are smaller than the male but have a similar plumage and are unlikely to be told apart in the field.

They feed on fruits and insects,but they are known to take small birds and their nestlings. They tend to forage singly or in pairs or occasionally in small flocks.They are sometimes encountered in mixed flocks with other fruit eating birds. The nest of this species is bowl-shaped consisting of twigs and some large leaves. It is generally situated two to three meters from the ground,among the bases of Pandanus trees or in the fork of a sapling. The female deposits a single egg.

Green catbird

Taken in Queensland Australia
Taken in Queensland Australia | Source

The Green catbird

Ailroedus crassirostris, is the Green Catbird, a species of Bower bird, found along the east coast of Australia from southeast Queensland to southern New South Wales.It is a very similar species to the Spotted Catbird,indeed some authorities believe they are the same species. They are medium sized,stocky birds with long powerful legs and a long stout bill. The back,wing and rump are a metallic emerald green and have a very conspicuous pure white spots. Spots also form white on the wing bars. The tail is a brownish emerald with a white tip.

The head is greenish brown mottled black and finely buff. The breast is a greenish buff to a dull emerald green with distinctive short white streaks. The legs are greyish brown. The bill is horn-coloured and there is a white eye ring.The sexes are the same .

The breeding season is generally from October to January,but varies according to weather conditions. The nest of this species is a large bulky affair,consisting of large twigs bound with vine tendrils with a lining of dry leaves. The nest is normally situated in the dense crown of low under-story trees,where the many tangled branches support the structure. Other sites such as the crown of a tree fern are also utilized.

The female will deposit two to three eggs,which she will incubate for a period of twenty three to twenty five days. The chicks which are fed by both parents will remain in the nest for a further twenty to twenty two days.

The diet of this species consists of fruit,particularly figs and also a variety of vegetable matter,such as buds,flowers and seeds supplemented by insects and other invertebrate,even the nestlings of smaller birds will be included. These birds are classed as being Vulnerable in New South Wales, however, they are birds of Least Concern on the IUCN list.

Spotted Catbird

Taken in Daintree, Queensland , Australia
Taken in Daintree, Queensland , Australia | Source

The Spotted Catbird

The Spotted Catbird , Ailuroedus melanotis,is a species found in north Queensland,Australia and on the Island of New Guinea and some surrounding islands. They are common and widespread over their large range. These birds are up to twelve inches long,they have a large dusky coloured head with a blackish cap and black ear patch.

The plumage on the upper parts are of a bright green colour with distinctive olive chevrons and a white streaking on the under parts. There are linear white wing bars and a green tail tipped with white. The beak is stout and cream coloured. The legs and feet are a dark to bluish-green. Both sexes are similar.

Despite it being referred to as a 'Bower bird' this species, like the former, builds a nest instead of a bower. The female alone undertakes the task of constructing the nest. The foundation is constructed of twigs around a lower nest cup. The lining is composed of dry leaves and vine tendrils. The eggs are incubated for twenty to twenty three days and generally two or sometimes three are deposited, the female carries out the task of incubating the eggs.

There are no current conservation concerns.

Spotted Catbird

Taken in Australia
Taken in Australia | Source

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4 comments

D.A.L. profile image

D.A.L. 6 months ago from Lancashire north west England Author

Hi Deb,

It is amazing how birds of the same name can vary so much and yet be equally fascinating. Thank you as always for your visit. Best wishes to you.


aviannovice profile image

aviannovice 7 months ago from Stillwater, OK

It is interesting to see that not all shrikes are created equally. These catbirds look nothing like the Gray Catbird from this country, but they are definitely more spectacular.


D.A.L. profile image

D.A.L. 7 months ago from Lancashire north west England Author

Hello Devika ,

You are welcome and thank you,as always , for your kind comments,always appreciated. Best wishes to you.


DDE profile image

DDE 7 months ago from Dubrovnik, Croatia

Wow! Incredible about birds. I often watch the birds picking their food from the ground. I find that a special moment. In the rain and windy days too. You have put together an interesting hub. As always you teach me more about these unique creatures. Thank you.

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