|Population||<20,000 (2011 est.)|
The southern cassowary (Casuarius casuarius) is a species of large, flightless bird of the family Casuariidae, and found on Papua New Guinea, northern Australia, and the Aru Islands, and characterized from other ratites by a bony crest on top of their heads.
It is the largest of the three species of cassowary, standing up to 6 feet high when fully erect, and can weigh up to 130 lbs; females are slightly larger than the males. 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 bare of feathers and brilliantly colored in blue, with a red double-wattle hanging near the base of the neck. 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.
The southern cassowary and its relatives also possess powerfully-muscled legs bearing three toed feet, 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 via a leaping jump forward in combination with a kick; the birds are capable of disemboweling a victim with one blow. Normally shy and retiring, cassowaries wandering into picnic and populated areas have in turn been given handouts, leading to changes in behavior, increasing aggressiveness, and cited for some 150 direct and indirect attacks against humans.
Eight subspecies have been proposed for C. casuarius over the years, based on minor genetic and physical differences. Current consensus indicates only one species, with no subspecies.
- Casuarius casuarius (casuarius)
- Casuarius casuarius (bicarunculatus)
- Casuarius casuarius (tricarunculatus)
- Casuarius casuarius (lateralis)
- Casuarius casuarius (sclaterii)
- Casuarius casuarius (aruensis)
- Casuarius casuarius (violicollis)
- Casuarius casuarius (johnsonii)
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.
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.
Man is the predominant threat to cassowaries. Logging, hunting, and automobile collisions within Queensland, Australia are responsible for the depletion in numbers of C. casuarius when it is found living near populated areas. 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.
- 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.