Roads cut through southern cassowary territories, making it necessary for the birds to travel across them when looking for food. Birds can also be attracted to roads by people feeding them or throwing litter from vehicles. Unrestrained and wild dogs are another major cause of southern cassowary mortalitu, particularly in areas near residential development. Chicks and sub-adults are small enough to be killed by dogs and packs of dogs also kill adult birds, pursuing them until they are exhausted, then attacking them.
Dogs also indirectly affect cassowaries through their very presence, influencing the feeding, movements and general behaviour of the birds. Domestic dogs can also attack and kill cassowaries when they wander into suburban areas seeking food or water.
Pigs cause disturbance to the rainforest and compete with cassowaries for fallen fruit. They may also eat southern cassowary eggs and destroy nests. Pig control activities may also be hazardous to cassowaries, particularly when dogs are let loose to hunt pigs, and end up finding and attacking cassowaries instead. Hand-feeding of cassowaries is a risk to both birds and people. Wild cassowaries conditioned to human food sources can be aggressive when protecting themselves or their chicks, or seeking other human food.
As birds become less wary of humans, they may become more vulnerable to dog attack and road mortality as they search for food. In recent years, cyclones have damaged large areas of southern cassowary habitat, causing temporary food shortages. This may place further stress on local populations already under threat from habitat fragmentation, dogs and vehicle strikes. The Recovery plan for the southern cassowary Casuarius casuarius johnsonii sets out actions to secure the long-term protection of the southern cassowary through improved habitat protection and enhancement, threat abatement and community engagement programs.
Local residents in southern cassowary areas are establishing nurseries of southern cassowary food plants to revegetate southern cassowary habitat on cleared land, and create corridors between existing patches of habitat.
The Department of Environment and Science has mapped the habitat of the southern cassowary. This information can then be considered when assessing future developments by state and local governments to protect southern cassowary habitat. A method for estimating southern cassowary abundance from genetic material in southern cassowary scats is being developed by the CSIRO. Recent work has shown that cells from the stomach lining of cassowaries are passed out in their scats, and collection and analysis of these scats, it may be possible to identify the sex and genetic code of each bird.
These results may help to estimate the size of populations, as well as how far birds move and their breeding patterns. Everyone can help protect our remaining cassowaries. If you live in or visit southern cassowary territory, follow these tips:. Cassowaries are not common and may be hard to find.
Photo Craig Allen. In scientists estimated the Australian population at 4, birds and numbers were declining. Cassowaries live in tropical rainforests, melaleuca paperbark swamps, mangrove forests woodlands and can even be found foraging along beaches. They require this diverse range of habitats to ensure availability of fleshy fruits year round.
They're capable swimmers, known to swim across rivers and into the sea to escape dog attacks. They're territorial , with a home range up to 2.
Cassowaries forage for fruits on the forest floor. Many species rely on cassowaries for seed dispersal and germination. For this reason they're known as a 'keystone' species. They've also been called a rainforest gardener, swallowing fruit whole and spreading the seeds great distances. They also occasionally eat small vertebrates, invertebrates, fungi and carrion dead animals. They breed when fruit is most abundant — from June to October.
The female lays three to five large green eggs in a simple nest scraped in the ground and lined with leaves. Once she's laid the eggs, the female leaves. The male then incubates the clutch for 50 days, raises and protects the chicks for about a year, and then chases them away.
Because the seeds are deposited in their own blob of fertiliser, they are able to germinate quickly, and through this action, Cassowaries assist with the regeneration of the rainforest. The Cassowary's large size, its large greyish helmet casque and the red wattle hanging from the neck, make it easy to identify. The feathers of the body are black and hair-like. The bare skin of the head and fore-neck is blue, while the rear of the neck is red.
Both sexes are similar in appearance, but the female is generally larger than the male, with a taller casque, and is brighter in colour. Young Cassowaries are browner than adults, and have duller coloured head and neck. The chicks are striped yellow and black. If a Cassowary is approached it will generally stand its ground. If the intruder approaches too close, the bird will stretch itself as tall as possible, ruffle its feathers and let at a loud hiss in an attempt to scare the intruder off.
The birds are equipped with quite dangerous claws, and will readily attack a persistent intruder, although they usually retreat into the dense rainforest. In appearance, the Cassowary looks like a short, heavily-built, black and blue Emu, Dromaius novaehollandiae.
Both species are indeed closely related, belonging to the family Casuariidae, and both are flightless. Southern Cassowaries are found in northern Queensland. The species is also found through New Guinea and eastern Indonesia. The dense habitat and the Cassowary's secretive nature make individuals difficult to see.
In certain areas birds come near human habitation seeking food. Throughout their range, Southern Cassowaries live alone, and inhabit the same area all year round. The Southern Cassowary feeds mostly on fruit that has fallen to the ground. The Southern Cassowary will also eat anything from snails to small dead mammals. Southern Cassowaries normally feed alone. If two males should meet, they have a stand off where both birds stand tall, fluff up their feathers and rumble at each other until one retreats.
If a male and female meet, the male will move away, as the female is dominant. Like ostriches, emus, rheas, and kiwis, cassowaries are ratites, flightless birds that possess a flat breastbone that is unable to support the muscles required for flight.
Cassowaries are typically solitary animals, but during the breeding season communicate through infrasonic booms low frequency sounds below the range of human hearing.
When in close proximity, cassowaries also communicate through subtle courtship behaviours, such as strutting in a circle, head shaking, throat and neck swelling, and high stepping to attract a mate.
Estimates of the population size for the southern cassowary suggest that the population is larger than previously expected. The population size of southern cassowaries, however, is decreasing.
Threats to the species historically included habitat loss and fragmentation for residential, agriculture, and commercial development in its Australian range.
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