Australo-Papuan babbler
Encyclopedia
The Pomatostomidae are small to medium-sized birds endemic to Australia-New Guinea. For many years, the Australo-Papuan babblers were classified, rather uncertainly, with the Old World babbler
Old World babbler
The Old World babblers or timaliids are a large family of mostly Old World passerine birds. They are rather diverse in size and coloration, but are characterised by soft fluffy plumage. These are birds of tropical areas, with the greatest variety in Southeast Asia and the Indian Subcontinent...

s (Timaliidae), on the grounds of similar appearance and habits. More recent research, however, indicates that they are too basal to belong the Passerida
Passerida
Passerida is under the Sibley-Ahlquist taxonomy, one of two "parvorders" contained within the suborder Passeri...

 - let alone the Sylvioidea
Sylvioidea
Sylvioidea is a superfamily of passerine birds. It is one of at least three major clades within the Passerida along with the Muscicapoidea and Passeroidea. It contains about 1300 species including the Old World warblers, Old World babblers, swallows, larks, bulbuls and perhaps the tits...

 where the Old World babblers are placed - and they are now classed as a separate family close to the Orthonychidae
Orthonychidae
The Orthonychidae is a family of birds with a single genus, Orthonyx, which comprises three species of passerine birds endemic to Australia and New Guinea, the Logrunners and the Chowchilla. Some authorities consider the Australian family Cinclosomatidae to be part of the Orthonychidae...

 (logrunners). Five species in one genus are currently recognised, although the red-breasted subspecies rubeculus of the Grey-crowned Babbler may prove to be a separate species. Further investigation is required.

Description

The Australo-Papuan babblers are medium-sized terrestrial birds with sombre plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...

 and long decurved bills
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...

. They range in size from 17–27 cm (7–11 in) in length and 30-85 g (1-3 oz) in weight. The wings are short and round, and the tail is long and often held fanned which makes it look broad as well. The feet and legs are strong and adapted to a terrestrial existence. There is no sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...

 in the plumage, which is composed of brown, russet and grey colours, with all but the Papuan Babbler having striking white markings on the face and throat. The plumage of juvenile birds is similar to that of adults.

Behaviour

All five species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 are ground-feeding omnivores and highly social. Babblers live in family groups and small flocks of up to about 20 individuals and forage communally, calling loudly to one another all day long. They feed principally on insects and other invertebrates, but will also take seeds, fruits and small vertebrates. Most food is obtained on the ground, although they will also forage in low bushes; the Grey-crowned Babbler
Grey-crowned Babbler
The Grey-crowned Babbler is a species of bird in the Pomatostomidae family.It is found in Australia, Indonesia, and Papua New Guinea....

 and Papuan Babbler feed more extensively in vegetation than the other species. The long bill is used to probe and overturn large objects. They will also hold objects with one foot and hammer them with the bill in order to extract food.

Breeding

Australo-Papuan babblers are monogamous
Monogamy
Monogamy /Gr. μονός+γάμος - one+marriage/ a form of marriage in which an individual has only one spouse at any one time. In current usage monogamy often refers to having one sexual partner irrespective of marriage or reproduction...

 breeders which defend territories. The breeding pair will be aided in breeding by a number of helpers from its group. A number of groups may have more than one breeding pair. Extra male helpers aid the male in his responsibilities whereas the females aid the main breeding female in hers. They have an extended breeding season. Australo-Papuan babblers construct large nests
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...

 for communal roosting, and these nests may be used for breeding, or new nests may be constructed. There may be a large number of nests used by the group in a small area. When the female is breeding she alone uses the breeding nest. Nest construction, both of roosting and breeding nests, is undertaken by all birds in the group. Between one to six eggs are laid (the number and range varies by species) and are usually incubated
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...

 by the breeding female alone (although a helper female may aid occasionally). The Breeding male and other helper males feed the breeding female during incubation. Incubation lasts between 19–25 days. The female broods the chicks until they are able to thermoregulate, and the chicks fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...

 after 16–23 days. After leaving the nest the chicks will continue to be fed by the adults for a number of months.

Species of Pomatostomidae

  • Papuan Babbler, Pomatostomus isidorei
  • Grey-crowned Babbler
    Grey-crowned Babbler
    The Grey-crowned Babbler is a species of bird in the Pomatostomidae family.It is found in Australia, Indonesia, and Papua New Guinea....

    , Pomatostomus temporalis
  • White-browed Babbler
    White-browed Babbler
    The White-browed Babbler is a species of bird in the Pomatostomidae family.It is endemic to Australia.Its natural habitat is Mediterranean-type shrubby vegetation.-References:...

    , Pomatostomus superciliosus
  • Hall's Babbler
    Hall's Babbler
    Hall's Babbler is a species of bird in the Pomatostomidae family. It is endemic to Australia and was first described in 1964.-Name:...

    , Pomatostomus halli
  • Chestnut-crowned Babbler
    Chestnut-crowned Babbler
    The Chestnut-crowned Babbler is a species of bird in the Pomatostomidae family.It is endemic to Australia.A cooperatively breeding bird living in social groups ranging from three to approximately twenty birds...

    , Pomatostomus ruficeps

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK