Family POMATOSTOMIDAE Schodde, 1975

Museums

Regional Maps

• Pomatostominae Schodde, R. 1975. Interim List of Australian Songbirds. Passerines. Melbourne : Royal Australasian Ornithologists Union vi 46 pp. [33].

  Type genus:

   Pomatostomus Cabanis, 1851.

  Secondary source:

   Boles, W.E. 1989. Correct authorship of Pomatostomidae. Auk 106(2): 341 [Date published 26 Apr 1989] [341] (correction of authorship from Sibley, Ahlquist & Monroe (1988)).

Introduction

With its centre of biodiversity on the Australian mainland, this small group of gregarious insectivores, the babblers, share convergent features with Old World babblers (Timaliidae). Thus, they have long scimitar-shaped bills and terrestrial, scansorial and arboreal behaviour. The family comprises two genera and is restricedt to Australia and New Guinea. Only Pomatostomus is found in Australia (but absent from Tasmania), with four species and eight ultrataxa. This genus is shared with New Guinea through one species, the Grey-crowned Babbler, P. temporalis. The other genus, Garritornis, comprises a single New Guinea endemic species. All Australian species are soberly plumaged with grey and russet browns interspersed by white on the throat or as a superciliary stripe, and all have a narrow white tip to the tail's extremity.

All species feed by gleaning or probing actions through terrestrial, scansorial and arboreal areas. By nature they are highly gregarious, their family groups participating in social feeding, roosting and nesting. 'They are noisy and active …, and are usually encountered in animated flocks that stay close together when feeding, roosting or escaping predators' (Boles 1988). Many species lead sedentary lives whereas others tend to have local nomadic movements. The family groups inhabit a variety of vegetation forms including woodlands, steppes, forests, heaths, mallee, and mulga with occasional forays into human habitation.

They are acknowledged nest builders and their large stick structures have varied uses. The domed nests are heavily constructed and placed in the uppermost limbs of trees and shrubs. Each nest has an extended entrance giving the appearance of a long-necked bottle. Nests have fine lining of fibrous material, grasses and feathers. Several birds attend the nest, sharing incubation and feeding duties. Egg clutches are normally two or three although multi clutches — where two or more females lay in the same nest — are not uncommon. Nests are also used for roosting and old nests dispersed throughout a group's territory often become dormitories for the wandering party.

Diagnosis

'Although Australian babblers have a single deep trabeculated fossa in the head of the humerus like other members of the Australian corvoid radiation, and conventional palates with emarginate, shortly bifid vomers, there similarities to other song-birds end. The keels on their sterna are shallow, and terminal processes on the ilium much attenuated and up-curled, both signs of living on the leg rather than the wing. Babblers fly low and laboriously from cover to cover, with much direct gliding. Features of the skull, in combination, are unique. Temporal fossae are oblate, flanked by a short, blunt postorbital process and short, but multiple-crested zygomatic process. Interorbital perforations are rectangular, and the naris is aperturate, with thin nasal bars; but descending into the nasal cavity from the roof of the nasal is an extraordinarily convoluted vestige of the internasal septum. This protuberance, of the same form in all species, extends back to articulate with the tip of the vomer. The ectethmoid plate is equally divergent. Narrowly winged and seemingly thick, it is deeply concave on the ventral face, with a massive sulcus; lachrymals are missing.'

Diagnosis References

Schodde, R. & Mason, I.J. 1999. The Directory of Australian Birds : Passerines. A Taxonomic and Zoogeographic Atlas of the Biodiversity of Birds in Australia and its Territories. Collingwood, Australia : CSIRO Publishing x 851 pp.

General References

Boles, W.E. 1988. The Robins and Flycatchers of Australia. Sydney : Angus and Robertson.

History of changes