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Australian Chats Epthianurinae
a subgroup of the HONEYEATERS Meliphagidae |
- 5 species in Australia
- DR personal total: 5 species (100%), 3 photo'd
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The
Australian Chats are five species of smallish, chat-like, sexually
dimorphic birds that walk rather than hop on the ground. These are
mostly birds of the dry interior of Australia, although some inhabit
coastal lagoons. In the great Australasian radiation, during which many
types of birds evolved in isolation for eons, they might be considered
the "pipit" equivalent. [Later, a pipit colonized Australia from Asia
and evolved into its own species: Australasian Pipit Anthus novaeseelandiae.]
They have been traditionally considered a separate family, but recent
molecular evidence has shown they evolved within the the Honeyeater
radiation, and are a deeply embedded within the family Meliphagidae;
Sibley & Monroe (1990), Christidis & Boles (1994), and
Dickinson (2003). At most, they are a subfamily.
Four species of Australian chats are in the genus Epthianura, including the Yellow Chat
(left; nice shot of a male by Hans & Judy Beste). It is one of the
hardest to find, being patchily distributed in saltbush lagoons of
northern Australia (Bakers et al. 1984). Because its locales are often
hard to reach, and even when reached it is inconspicuous in behavior,
it remains a little known species. The other Epthianura species are more widespread: Orange E. aurifrons, Crimson E. tricolor [see photo on Honeyeater page], and White-fronted E. albifrons Chats.
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The
major families in the great Australasian radiation were divided by
Sibley & Ahlquist (1990) between the menurids (including the
lyrebirds, scrub-birds, honeyeaters and relatives) and the corvoids
(crows, birds-of-paradise, butcherbirds and numerous relations). The
Australian chats were placed in the menurid group and, in fact, Sibley
& Ahlquist (1990), Sibley & Monroe (1990) considered them
simply aberrant honeyeaters. The have brush-tipped tongues, presumably
evolved for nectar feeding when there are blooms in the arid interior,
but these chats eat mostly insects (Blakers et al. 1984, Simpson &
Day 1996). Although brush-tipped tongues could be an example of
convergent evolution, it is often cited as evidence for their
relationship with honeyeaters. DNA-DNA hybridization supported this
view (Sibley 1996), which has since been confirmed by more advanced
molecular studies (Driskell & Christidis 2004) and widely accepted
(e.g., Dickinson 2003). Its sister group is uncertain, but Ramsayornis honeaters (e.g., Bar-breasted and Brown-backed Honeyeaters) are among the closer relatives (Driskell & Christidis 2004).
In
more traditional taxonomies (e.g., Frith 1976, 1979; Blacker et al.
1984, Simpson & Day 1984), the "Epthianuridae" were considered a
separate family that was placed near the honeyeaters. Apparently, the Handbook of the Birds of the World
(HBW) project will continue to elevate the group to family status,
despite the new evidence, to emphasize their uniqueness and because
changes in phylogeny have been taking place so rapidly that a
long-planned series like HBW cannot keep up, in practical terms. Given
the arboreal habitats of the vast majority of honeyeaters, the
terrestrial chats are, indeed, quite different birds. It makes sense
for world birders to specially seek them out as a distinctive group,
even if no longer a family. |
The remaining species in this family is in its own genus (Ashbyia) and used to be known as the "Gibberbird"; it is now often called Gibber (or Desert) Chat
(right in another fine Hans & Judy Beste photo). It is a
terrestrial bird of stony desert and short grass plains in south-east
central Australia: the Gibber plains. It stands upright on rocks, like
a wheatear, but wags its tail like a pipit.
All the
Australian chats are arid adapted species and therefore nomadic to some
degree. In the non-breeding season, mixed flocks of chats are sometimes
encountered, and some small flocks can wander very widely. In the
breeding season some species (e.g., White-fronted) nest in loose
colonies but territories are well defended from each other. Chats tend
to erupt and breed after after rains. Thus the breeding range of some
species, such as Crimson Chat, can be wildly different year-to-year.
Orange Chat may be the most tolerant of desiccation (Blakers et al.
1984) and can be found in very arid spinifex, saltbush, and tussock
grass. This may be the reason its breeding range is less volatile year
in and year out. The White-fronted and Yellow Chats are more adapted to
water edges, with Yellow especially restricted to sedge or saltbush
swamps. White-fronted Chat inhabits heathland and pasture but, like all
the chats, feeds primarily on the ground.
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Photos: The male Yellow Chat Epthianura crocea was photographed by Hans & Judy Beste near the South Alligator River, Northern Territory, Australia, in 1980. The Gibber Chat Ashbyia lovensis
was at Tibooburra, in extreme northwestern New South Wales, in 1971.
Photos © Don Roberson, except that attributed to Hans & Judy Beste and used with permission; all
rights reserved.
Bibliographic note: There was no family book when this was more or less universally accepted as a family, and the Handbook of the Birds of the World has not yet reached this group. It is my understanding that HBW will treat it as a family, notwithstanding new research, for traditional purposes.
Literature cited:
Blakers,
M., S.J.J.F. Davies, and P. N. Reilly. 1984. The Atlas of Australian
Birds. Royal Australian Ornith. Union, Melbourne Univ. Press, Carlton,
Victoria.
Christidis, L., and W.E. Boles. 1994. The
taxonomy and species of Birds of Australia and its territories.
A.A.O.U. Monograph 2: 1-112.
Dickinson, E., ed.
2003. The Howard & Moore Complete Checklist of the Birds of the
World. 3d ed. Princeton Univ. Press, Princeton, N.J.
Driskell,
A.C., and L. Christidis. 2004. Phylogeny and evolution of the
Australo-Papuan honeyaters (Passeriformes, Meliphagidae). Molec.
Phylog. Evol. 31: 943-960.
Frith, A.J. 1976, 1979. Reader's Digest Complete Birds of Australia. Reader's Digest, Sydney, Australia.
Sibley, C.G. 1996. Birds of the World, on diskette, Windows version 2.0. Charles G. Sibley, Santa Rosa, CA.
Sibley, C.G., and J.E. Ahlquist. 1990. Phylogeny and Classification of
Birds: A Study in Molecular Evolution. Yale Univ. Press, New Haven, CT.
Sibley, C.G., and B.L. Monroe, Jr. 1990. Distribution and Taxonomy of Birds of the World. Yale Univ. Press, New Haven, CT.
Simpson, K, and N. Day. 1984. A Field Guide to the Birds of Australia, 1st ed. Tanager Books, Dover, N.H., USA.
Simpson, K, and N. Day. 1996. A Field Guide to the Birds of Australia,
revised 5th ed. Penguin Books Australia Ltd., Ringwood, Victoria,
Australia.
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