Artamidae

Artamidae
File:Piedbutcherbird.jpg
Pied butcherbird
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Suborder:	Passeri
Superfamily:	Malaconotoidea
Family:	Artamidae C. G. Sibley & J. A. Ahlquist, 1990
Subfamilies
Cracticinae Artaminae File:Distribution map of Artamidae.jpg Map showing all the known Artamidae sittings in Australasia

Artamidae is a family of passerine birds found in Australia, the Indo-Pacific region, and Southern Asia. It includes 23 extant species in four genera and two subfamilies: Artaminae (with only one genus, the woodswallows) and Cracticinae (currawongs, butcherbirds, and the Australian magpie). Artamids used to be monotypic, containing only the woodswallows, but it was expanded to include the family Cracticidae in 1994. Some authors, however, still treat the two as separate families. Some species, known for their beautiful song, are in this family. Their feeding habits vary from the harmless nector sucking of the woodswallows to the fearless predation on small birds from the pied currawong.

Taxonomy and Systematics

The Artamids are part of the Malaconotoidea superfamily, consisting of a vast diversity of omnivores and carnivorous songbirds wide spread through Australasia. Artamids has been divided over time into two subfamilies. With little studies and dispute on the inclusion of Cracticidae to the Artamidae family, it appears they have been placed in this respective joint position due to lack of evidence or knowledge. Jerome Fuchs and colleagues extensively analysed both the mitochondrial and nuclear DNA of the Artamid family. The results suggested that the group may have existed in Australasia for 33.7 to 45 million years, dating back to the late Eocene

Distribution and Habitat

Artamid species occur throughout Australasia with most species occurring in Australia and New Guinea. The social interactions of Artamids vary from the solitary black butcherbird, who lives alone or in a single pair, to the white-breasted woodswallow who lives in flocks or loose colonies. While some species are sedentary, staying close to suburbia and ample food sources, others are migratory or even nomadic like the Masked woodswallow, moving around in response to changes in climate such as rainfall or temperature. Their range of habitats varies between species but most will adapt to rain forests, woodlands, coastal scrubs (swallows), water courses, playing fields, pastoral lands and paperbark mangroves (butcher birds). One of their greatest abilities is to adapt to urban landscapes where they contend with fragmented and degraded remnants of native vegetation.

Morphology

File:Aus Magpie morphology.JPG

The Australian Magpie showing its plumage.

Artamids are a diverse family possessing a notable variation in size and shape. Ranging in size from the short stocky Fiji woodswallow Artamus mentalis and the Ashy woodswallow Artamus fuscus, both of which are around 19 cm in length and weigh about 40 g, to the larger built grey currawong Strepera versicolour, which measures up to 50 cm and weighs up to 440g. The beaks of artamids are strong and robust, sometimes known as a generalist beak. Alike falcons, some of the Subfamily Cracticinae possess a sharp projection along the upper mandible, with a corresponding notch on the lower mandible. This hook like tooth is used to catch and fatally sever insects, lizards and small mammals apart. A distinguishing trait of artamids (all passerines) is that it possesses an anisodactyl foot arrangement. This means that three toes are directed forward and one toe directed backward. This enables them to perch on vertical objects like tree branches and power lines.

Due to the possession of a syrinx, Artamids are able to create subtle songs, in particular the pied butcherbird, the pied currawong and the Australian magpie. Another unique trait, among other perching birds, is that some woodswallows possess special feathers called powder down. The tips of the barbules on powder down feathers disintegrate, forming fine particles of keratin, which appear as a powder, or "feather dust", among the feathers and spread when preening. The plumage of the Artamids is relatively dull with most birds using a combination of greys, earthy browns, blacks and patches of whites. There is seldom-sexual dimorphism in plumage, when it occurs the males are brighter and the females appear dull or resemble juveniles. In many species juveniles have a distinctly duller plumage. The notarium, being fused vertebra of the shoulder in birds that helps brace the chest against the forces generated by the wings, is a distinctive osteological trait that has evolved repeatedly in the passerines including the Artamadae family.

Behaviour

Members of the Artamidae, especially the woodswallows, have been known to cluster together during the night and day. Accounts have appeared in literature from the earliest days of ornithological documentation in Australia. The habit of clustering is believed to serve two purposes being the retention of body heat during the cooler weather and a social form of camouflage. Another unusually behaviour by an Artamid is the swooping of humans by magpies. While there is not much information on this behaviour, previous studies have suggested that Magpie attacks on humans may be strongly influenced by hormone levels. However, recent investigations indicate that the stress hormone corticosterone may cause magpie aggression and swooping.

Diet and feeding

All are omnivorous to some degree: the butcherbirds mostly eat meat; Australian magpies usually forage through short grass looking for worms and other small creatures; currawongs are true omnivores, taking fruit, grain, meat, insects, eggs and nestlings and woodswallows feed on insects and nectar. Most are opportunistic feeders, such as the woodswallows, taking advantage of the flowering plants such as the silky oak Grevillea robusta, box mistletoe Amyema miquelii, and the long flowering stalks of Xanthorrhoea spp or insects such as cockroaches or spiders eaten by the black butcherbird. Bigger species like the grey currawong preys on many vertebrates, including frogs, lizards such as skinks and juveniles of smaller birds such as the native eastern spinebill Acanthorhynchus tenuirostris or the introduced house sparrow Passer domesticus, The evolution of vertical feeding zones (feeding strategies subdividing into vertical space, e.g. upper, mid and ground canopy) is noted in the artamid family. While species will sometimes overlap vertical terrains most woodswallows will use the upper canopy, feeding on insects and pollen, while magpies and currawongs tend to use the ground or swoop down from the mid story pouncing on their food. Being accomplished in extractive foraging is another trait of the artamid. While being opportunistic feeders they are very methodical forages, often following a set routine. ,

Threats

Habitat loss

File:Australian magpie subject to roadkill, a threat to ArtamidaeJPG.JPG

A picture of a roadkill magpie.

With developments occurring more regularly the most critical threat to the artamids is habitat destruction and habitat fragmentation. This loss of habitat reduces vegetation corridors (connective parcels of vegetation) that are used for feeding, breeding and safely travelling. After fragmentation, habitats are often too small or are limited by the construction of roads. These barriers that cause populations stresses and species can become vulnerable to localised extinction. Habitat loss and fragmentation can force species into urbanised habitats that impose their own dangers such as cars. Roadkill is considered to significantly contribute to the population decline of many species, especially opportunistic feeders like the Artimade. Often unconsciously swooping down on an insects with out seeing an on coming car.

Introduced species

In Australia introduced species have caused the greatest number of extinctions. Exotic feral animals such as cats can have a negative effect on the artamids. Ground foraging species such as the magpie can often fall prey to an unsuspecting cat in urban environments.

Species of Artamidae

There are two subfamilies with four genera recognised. In 2013 a molecular study has shown The Australian magpie to be the sister taxon to the black butcherbird however it is still classified in its own genus (C. quoyi).

• Subfamily Cracticinae:
  • Genus Peltops
    • Mountain peltops, Peltops montanus
    • Lowland peltops, Peltops blainvillii
  • Genus Cracticus
    • Australian magpie, Cracticus tibicen
    • Black butcherbird, Cracticus quoyi
    • Hooded butcherbird, Cracticus cassicus
    • Tagula butcherbird, Cracticus louisiadensis
    • Pied butcherbird, Cracticus nigrogularis
    • Black-backed butcherbird, Cracticus mentalis
    • Grey butcherbird, Cracticus torquatus
  • Genus Strepera
    • Pied currawong, Strepera graculina
    • Black currawong, Strepera fuliginosa
    • Grey currawong, Strepera versicolor
• Subfamily Artaminae:
  • Genus Artamus
    • Ashy woodswallow, Artamus fuscus
    • Fiji woodswallow, Artamus monachus
    • Ivory-backed woodswallow, Artamus monachus
    • Great woodswallow, Artamus maximus
    • White-breasted woodswallow, Artamus leucorynchus
    • White-backed woodswallow, Artamus insignis
    • Masked woodswallow, Artamus personatus
    • White-browed woodswallow, Artamus superciliosus
    • Black-faced woodswallow, Artamus cinereus
    • Dusky woodswallow, Artamus cyanopterus
    • Little woodswallow, Artamus minor