Cassowaries are found only in north Queensland and Papua-New Guinea. The cassowary’s origins trace back to prehistoric times when Australia was part of the huge Gondwana continent. Although it is a large, powerful and aggressive bird, development of its once virginal, rainforest domain has forced the cassowary into the endangered zone and the locals do all they can to protect this remarkable bird.
Whilst they can be somewhat elusive, the resident Cassowary at Etty Bay can always be seen around the beach. Another good place where you are virtually guaranteed to see one is the short, tranquil walk at Lacey’s Creek on the way to Mission Beach from El Arish.
Extremely territorial, contact between adults generally only occurs during mating. From May to November, pairs of cassowaries court briefly, mate and then separate. A female can mate with several males in one season. Females lay between three to five large, olive-green eggs, generally between June and October. Eggs are incubated by the male for about 50 days, and they guard the eggs and raise the chicks. Juveniles begin to fend for themselves from about eight to 18 months of age, when they are chased away by the male. They can be dangerous when cornered with chicks.
Usually solitary animals, cassowaries live in a home range that fluctuates depending on season and availability of food. The size of observed home ranges have varied between 0.52 km2 to 2.35 km2. The home range of a female southern cassowary usually overlaps with the home ranges of several males. Cassowaries are territorial, and c
As tall as a person, the adult southern cassowary has a tall, brown casque (helmet) on top of its head, a vivid blue and purple neck, long drooping red wattles and amber eyes. The purpose of the tall helmet or casque is unknown but it may indicate dominance and age, as it continues to grow throughout life. Recent research indicates it may also assist cassowaries in “hearing” the low vibrating sound made by other cassowaries. The casque is spongy inside, rather than bony, and may also act as a shock-absorber that protects the bird’s head when it pushes through dense thickets of rainforest and scrub.
The southern cassowary has coarse hair-like feathers with no barbules, and also lacks tail feathers. Its wing stubs carry a small number of long, modified quills which curve around the body. Each heavy, well-muscled leg has three toes, with the inside toe bearing a large dagger-shaped claw (up to 120 mm long) used for scratching and fighting other birds.
Newly-hatched chicks are striped dark brown and creamy white. After three to six months the stripes fade and the plumage changes to brown. As the young mature, the plumage darkens, the wattles and casque develop and the skin colour on the neck and wattles brighten. Cassowaries reach maturity at about three years of age.
Adult cassowaries can grow to an imposing 2 m tall. In general, the sexes are fairly similar in appearance, though females are slightly larger and can weigh up to 76 kg. Males can weigh up to 55 kg.
In the Wet Tropics cassowaries are distributed widely from Cooktown to Paluma Range. Approximately 89% of their remaining essential habitat in the Wet Tropics lies within protected tenures. Southern cassowary habitat in the Wet Tropics have been greatly reduced by land clearing and, cassowary numbers have also decreased.
Did you know?
- The southern cassowary is Australia’s heaviest flightless bird, but the emu is taller.
- It is an important rainforest gardener, spreading the seeds of rainforest trees. Sometimes the seeds are so large that no other animal can swallow and disperse them.
- Cassowaries require a high diversity of fruiting trees to provide a year-round supply of fleshy fruits. Although occurring primarily in rainforest, they also use woodlands, melaleuca swamps, mangroves and even beaches, both as intermittent food sources and as connecting habitat between more suitable sites. Places with a mix of these environments are preferred by cassowaries that live near the coast.
- Cassowaries prefer fallen fruit, but will eat small vertebrates, invertebrates, fungi, carrion and plants. Over 238 species of plants have been recorded in the southern cassowary diet.
Cassowaries play an important role in maintaining the diversity of rainforest trees. Cassowaries are one of only a few frugivores (fruit eaters) that can disperse large rainforest fruits, and the only species that can carry large seeded fruits over long distances.
- They swallow the fruit whole, digesting the pulp and passing the seeds unharmed in large piles of dung, distributing them over large areas throughout the rainforest. Some rainforest seeds even require the southern cassowary digestive process to help them germinate. Southern cassowary scats are large and often containing hundreds, if not thousands of seeds. A ready-made fertiliser, the dung helps many kinds of seed to grow. White-tailed rats, bush rats, melomys and musky rat-kangaroos sometimes feed on seeds in southern cassowary droppings, helping to further distribute the seeds.
The Wet Tropics (or southern) population is listed as Endangered in Queensland (Nature Conservation Act 1992) and it is ranked as a critical priority under the Department of Environment and Science.