>Struthidea cinerea (Apostlebird)

Apostlebird

Apostlebird
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Corcoracidae
Genus:	Struthidea Gould, 1837
Species:	S. cinerea
Binomial name
Struthidea cinerea Gould, 1837

The Apostlebird (Struthidea cinerea), also known as the Grey Jumper, is a quick-moving, gray or black bird about 13 inches (33 centimetres) long. It is a native to Australia where it roams woodlands, eating insects and seeds at, or near, ground level. Apostlebirds often travel in groups of about 12; for this reason they were named after the Biblical apostles, the twelve chief followers of Jesus Christ.

Taxonomy

Originally described by ornithologist John Gould in 1837, its specific epithet is Latin cinerea "grey". In its own genus Struthidea, it is placed in the family known as the mud-nest builders or Corcoracidae, written as Grallinidae in older books before the removal of the genus Grallina to the Wagtail family. It is one of two remaining species, with the White-winged Chough (Corcorax melanorhamphos), which differs in appearance but exhibits many behavioural similarities.The mudnest builder family Corcoracidae itself is now placed in a narrower "Core corvine" group, which contains the crows and ravens, shrikes, birds of paradise, fantails, monarch flycatchers, and drongos.

The Apostlebird was named after the Biblical apostles, the twelve followers of Jesus Christ. In fact, the species travel in family groups of between 6 and 20, which may coalesce with other family groups into large feeding flocks of over 40. Their gregarious nature, and harsh scolding/grating calls have led to a plethora of colloquial names. They can be known locally as Lousy Jacks (due to heavy louse infestations), Happy Jacks,Happy Families and CWA Birds. The latter name is mildly derogatory, referring to the supposed resemblance of Apostlebird's constant chatter to a Country Women's Association meeting. Grey Jumper is an alternate name.

Description

Measuring around 33 cm (13 in) in length, the Apostlebird is a predominantly dark grey bird with a long black tail tinted greenish in sunlight. The grey feathers on the head, neck and breast are brushed with paler grey-white and the wings are brownish. The legs and bill are black and the eyes brown or white.

Distribution and habitat

The natural range is across inland eastern Australia, from the mallee regions of northern Victoria and eastern South Australia, north through New South Wales and central-western Queensland to the Gulf Country. There is an isolated population in the Northern Territory. Dry open woodland is the preferred habitat, especially Callitris  in New South Wales and Casuarina in Queensland, and Lancewood-Bulwaddi communities in the Northern Territory.

Breeding

Mud nest high in a Kurrajong tree

Apostlebirds are a socially living, cooperative breeding species with each breeding group generally containing only one breeding pair, the rest being either their helper offspring, kin or unrelated adult birds. Most group members help construct a mud nest, share in incubation of the eggs, and defense of the nest. Once the eggs are hatched, all members of the group help feed the chicks and keep the nest clean.

Apostlebirds are a fission-fusion society. In winter, birds flock in larger groups, and as breeding season approaches winter groups break into smaller breeding groups. This change in group size is a consequence of breeding groups merging in the winter and breaking apart again in the summer breeding season. Breeding groups use small, non overlapping home ranges around the nest site, while winter ranges are larger with groups freely interacting with other groups[9].

Breeding season is from August to December. The nest is a deep cup-shaped structure made of grasses held together with mud or sometimes manure in a tree fork up to seven or eight metres above the ground. Three to five pale blue-white eggs sparsely splotched with brown and lavender shades are laid measuring 22 mm x 29 mm. They are tapered oval in shape.

Conservation status

Apostlebirds are not listed as threatened on the Australian Environment Protection and Biodiversity Conservation Act 1999. However, their conservation status varies from state to state within Australia. For example:

• The Apostlebird is listed as threatened on the Victorian Flora and Fauna Guarantee Act (1988). Under this Act, an Action Statement for the recovery and future management of this species has not yet been prepared.

• On the 2007 advisory list of threatened vertebrate fauna in Victoria, the Apostlebird is not listed as a threatened species.

>Corcorax melanorhamphos (White-winged Chough)

White-winged Chough

White-winged Chough
Perched on a eucalypt
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Corcoracidae
Genus:	Corcorax Lesson, 1831
Species:	C. melanorhamphos
Binomial name
Corcorax melanorhamphos (Vieillot, 1817)

The White-winged Chough (Corcorax melanorhamphos) is one of only two surviving members of the Australian mud-nest builders family, Corcoracidae, and is the only member of the genus Corcorax. It is native to Southern and Eastern Australia and is an example of convergent evolution as it is only distantly related to the European choughs that it closely resembles in shape, and for which it was named.

Taxonomy

The White-winged Chough was first described by French naturalist Louis Jean Pierre Vieillot in 1817 as Coracia melanorhamphos, other names given include Pyrrhocorax leucopterus by Dutch zoologist Coenraad Jacob Temminck in 1820, and Corcorax australis by French naturalist René-Primevère Lesson in 1830. before the current name was settled by Gregory Mathews in 1912. The specific epithet is derived from the Ancient Greek words melano- 'black' and rhamphos 'beak'.

It is placed in the family known as the mud-nest builders or Corcoracidae, written as Grallinidae in older books before the removal of the genus Grallina to the family Monarchidae. It is one of two remaining species, with the Apostlebird (Struthidea cinerea), which differs in appearance but exhibits many behavioural similarities. The mudnest builder family Corcoracidae itself is now placed in a narrower 'Core corvine' group, which contains the crows and ravens, shrikes, birds of paradise, fantails, monarch flycatchers, and drongos.

It is only distantly related to the European Chough (Pyrrhocorax pyrrhocorax), and Alpine Chough (P. graculus), which are members of the crow family Corvidae. The similarities in appearance of dark plumage and downturned bill are the result of convergent evolution.

Description

Landing on a branch in Brisbane Ranges National Park, Australia

White-winged Choughs are easily recognised but often mistaken for "crows"—a double mistake, as the birds most frequently called "crows" in Australia are actually ravens (see Australian Raven and Little Raven). The White-winged Chough is a large, black bird—at about 45 cm (18 in) only a little smaller than a raven or a little larger than an Australian Magpie—but has red eyes and a finer, slightly down-curved beak, similar to a European Chough. These red eyes become swollen and brighter in colour when the bird is excited. In flight the large white patches in the wings are immediately obvious, and explain the descriptive part of their common name.

Their calls consist primarily of a grating alarm call and a descending piping call. The latter call is diagnostic for the bird in the wild, being significantly different in timbre and melody to that of other birds sharing their habitat.

Behaviour

On the search for food in short grass

Flight is a mixture of a slow, deep flapping and short glides: unlike their European namesakes, White-winged Choughs are not particularly strong or agile fliers and spend the great majority of their time on the ground, foraging methodically through leaf litter for worms, insects, grain, and snails in a loose group, walking with a distinctive swagger, and calling softly to one another every few seconds. A rich find is the cause of general excitement and all come running in to share in it. The family group walks several kilometers each day through its large territory, foraging as it goes, taking to the air only if disturbed.

Choughs are territorial and highly social, living in flocks of from about 4 up to about 20 birds, usually all the offspring of a single pair. Because raising of young is a group effort bands of chough may kidnap fledglings from other family groups so that they will be able to help them to raise their chicks next year.

Feeding

Foraging in short grass this bird has found a small beetle

A group searching for food

The White-winged Chough will forage in litter and rotten wood for termites and beetles. Although birds have eaten pieces of apple placed out for them on feeding tables, they have not been recorded eating fruit on trees.The diet is varied, the White-winged Chough eats seeds of various grasses (Poaceae),Gahnia grandis, Atriplex,  
Epacris,  Hibbertia, Solanum, Acacia and Exocarpos species, as well as introduced species such as the Cursed Thistle (Cirsium arvense), Roadside thistle (C. vulgare), Winter Honeysuckle (Lonicera fragrantissima), Convulvulus and Oxalis species. Berries of the introduced Cotoneaster and Crataegus are also consumed. It eats a wide variety of arthropods, including centipedes, millipedes and many types of insect—beetles, cockroaches, termites, grasshoppers
and crickets, flies, butterflies and moths, and ants, bees and wasps.

Breeding

Nesting and breeding is communal, all members of the family helping to raise the young - a process that takes several years, as young birds must learn the art of finding food in the dry Australian bush. Larger families have a better chance of breeding success: so much so that given the opportunity choughs will kidnap the youngsters of neighboring families in order to recruit them to the team: the more helpers the better!Breeding season is from August to December. The nest is a deep cup-shaped structure made of grasses held together with mud or sometimes manure in a tree fork up to 10 metres above the ground. Three to five cream-coloured eggs sparsely splotched with dark brown and lavender shades are laid measuring 30 mm x 40 mm.

There is one report of White-winged Choughs occupying and using a nest which was likely to have been built by the Australian Magpie. However, this was unable to be confirmed as the nest was not witnessed being built.

All members of a family take turns to incubate, preen, and feed youngsters, and all cooperate in defending the nest against predators. However, the juveniles, who are highly inefficient foragers, have been observed to engage in deception; they bring food back to the nest and make to feed nestlings, but instead wait until unobserved, and then eat it themselves. This behaviour disappeared when food sources were artificially supplemented. There are three main threats to young choughs: starvation; predation by nest-robbing birds, particularly currawongs; and sabotage by neighbouring chough families anxious to protect their food supply by restricting competition. Larger family groups are better able to deal with all three threats.