Cassowary

Cassowary
Southern cassowary Casuarius casuarius
Scientific classification
Kingdom Information
Domain	Eukaryota
Kingdom	Animalia
Subkingdom	Bilateria
Branch	Deuterostomia
Phylum Information
Phylum	Chordata
Sub-phylum	Vetebrata
Infraphylum	Gnathostomata
Class Information
Superclass	Tetrapoda
Class	Aves
Sub-class	Neornithes
Infra-class	Eoaves
Order Information
Superorder	Palaeognathae
Order	Struthioniformes
Sub-order	Casuarii
Family Information
Family	Casuariidae
Tribe Information
Tribe	Casuariini
Genus Information
Genus	Casuarius
Species Information
Species	C. bennetti C. casuarius C. unappendiculatus
Population statistics

Cassowaries are three species of large, flightless birds of the family Casuariidae, and found on Papua New Guinea, northern Australia, and adjacent islands, and characterized from other ratites by a bony crest on top of their heads.

Description

Cassowaries, due to their shyness and forest habitat, are difficult to observe. They stand up to 6 feet high when fully erect, the female slightly larger than the male, and can weigh up to 130 pounds. Smaller than their close relative, the emu, they are stockier in appearance. The hair-like plumage is dark, almost black in color, and hangs loosely from the bird; since there are no barbules on the feathers, the barbs cannot link to form a vein. The rudimentary wings are hidden from view, a set of four or five stiff spine-like shafts about fifteen inches long indicating where they are.

The head and neck are brilliantly colored, mainly blue, but red and yellow are present, depending on the species. The head is crowned with a casque, a bony growth of keratin up to six inches in height. To date, no reasonable explanation has been put forward for the presence of the casque, which has been postulated as being a sound resonator, a sexual characteristic, or as an underbrush battering ram; indeed many cassowaries have been recorded showing damage to the casque, suggesting the plausibility of the battering ram theory. In his research Andrew L. Mack suggests the sound resonator may be correct, as the birds have a very low-frequency, booming call - as low as 23 Hz - necessary for communicating with each other in the dense, forested areas in which it is found.

Cassowaries also have a feature which has arguably made them the most dangerous birds in the world. The powerfully-muscled legs bear three toed feet, with the inner toe bearing a five-inch, nearly-straight claw. The claw functions as a defensive weapon, and the bird is known to attack anything it considers a threat. Handouts fed to them by people have led to changes in behavior, increasing aggressiveness, and cited for some 150 direct and indirect attacks against humans.

Species

• Dwarf cassowary, Casuarius bennetti
• Northern cassowary, Casuarius unappendiculatus
• Southern cassowary, Casuarius casuarius

Nesting

Cassowaries are basically solitary, coming together primarily to mate. The nest is barely a scraping on the forest floor, containing from three to eight eggs. After they are laid it is the males who incubate and rear the chicks until they are fledged. The chicks are a dull brown in color, broken by horizontal black bars; they gain their adult plumage within two years.

Diet

Despite its reputation as a dangerous bird, the cassowary is primarily a fruit eater. They pluck it from trees or pick up fallen fruit from the forest floor and swallow it whole; apples, plums, wild grapes, nightshade, and myrtle are part of the diet. When fruit is not available, or when the opportunity presents itself, cassowaries also take insects, small rodents, lizards, fish, and sometimes carrion.

Threats

Man is the predominant threat to cassowaries. Logging is responsible for the depletion of C. bennetti, while hunting is rather heavy for C. casuarius when it is found living near populated areas, whose numbers were also impacted as a result of automobile collisions. Hunting by native populations for cultural purposes is sporadic, and has no overall impact on numbers. In 2006 and 2011 Queensland was hit by cyclones, which destroyed habitat and killed a number of birds.

References

• Kofron, Christopher P. (1999). "Attacks to humans and domestic animals by the southern cassowary (Casuarius casuarius johnsonii) in Queensland, Australia." Journal of Zoology, 249, pp 375–381.