Cassowary
Flightless bird with a fearsome claw and a glowing casque.
Cassowaries, known in Indonesian as *kasuari* and in Tok Pisin as *muruk*, are flightless birds belonging to the genus *Casuarius* within the order Casuariiformes. As ratites, they lack a keel on their sternum bones. These birds are native to the tropical forests of New Guinea, the Moluccas (specifically Seram and the Aru Islands), and northeastern Australia. Three species are extant: the southern cassowary, the northern cassowary, and the dwarf cassowary. The southern cassowary is the most common and is the fourth-tallest and third-heaviest living bird, surpassed only by ostriches and the emu. The northern cassowary is the most recently discovered and the most threatened. A fourth, extinct species, the pygmy cassowary, is also known.
The genus *Casuarius* was established by French scientist Mathurin Jacques Brisson in 1760, with the southern cassowary as the type species. The name derives from the Malay *kasuari*. Cassowaries are part of the ratite group, which includes emus, rheas, ostriches, and kiwis, as well as extinct moas and elephant birds. Genetic evidence indicates that emus are their closest living relatives, and that the dwarf cassowary is more closely related to the northern cassowary than either is to the southern cassowary. Several subspecies have been proposed, but validation is difficult due to individual variation, age-related changes, and the long history of trading live cassowaries.
Typically shy and reclusive, cassowaries inhabit deep forest and are adept at avoiding humans. Females are larger and more brightly coloured than males. Adult southern cassowaries stand 1.5 to 1.8 meters tall, with some females reaching 2 meters, and weigh between 15 and 76 kilograms. The dwarf cassowary is much smaller. On the Aru islands, the southern cassowary is considered Asia's largest bird since the extinction of the Arabian ostrich, and within New Guinea, it is the island’s second largest terrestrial animal after introduced deer. Their feathers lack tail feathers and a preen gland, and their small wings have stiff, keratinous quills. They have no tongue, and their beaks are pointed and robust. Cassowaries possess three-toed feet with sharp claws; the inner toe bears a dagger-like claw up to 125 millimeters long, which they use to kick when provoked. They can run up to 50 kilometers per hour, jump 1.5 meters, and are strong swimmers. All three species
- field
- Ornithology
- known_for
- Being the world's most dangerous bird; producing the lowest-frequency bird call known
- species_count
- Three extant species: southern, northern, and dwarf cassowary
- height
- 1.5–2 m (4 ft 11 in to 6 ft 6+1⁄2 in)
- top_speed
- 50 km/h (30 mph)
- lifespan
- 18–20 years wild; up to 40 years in captivity
Lore & Background
Cassowaries are typically shy, solitary birds that inhabit deep tropical forests, where they are highly adept at evading detection by humans. They are capable of running at speeds of up to 50 km/h through dense vegetation, can leap as high as 1.5 meters, and are proficient swimmers, able to cross wide rivers and even swim in the sea. Their plumage consists of feathers with a shaft and loose barbules, lacking both tail feathers (rectrices) and a preen gland. Their small wings are reduced to stiff, keratinous quills resembling porcupine quills, with no barbs. The furcula and coracoid bones are degenerate, and the palatal and sphenoid bones touch, adaptations thought to help them move quickly through thorny, vine-filled rainforest. Unlike most birds, cassowaries have no tongue; their beaks are pointed, sharp, and robust but not serrated, suited for picking fruit. They possess three-toed feet with sharp claws, the inner toe bearing a dagger-like claw up to 12 cm long, used as a formidable weapon when they kick. All three species have a keratinous, skin-covered casque on the head that grows with age, its shape and size varying by species: the southern cassowary has the largest, the dwarf cassowary the smallest (tricorn-shaped), with the northern cassowary falling in between. The casque is hollow inside and spanned with fine fibres.
Reader's Guide
Cassowaries are significant as the largest bird in Asia (since the Arabian ostrich's extinction) and the second largest terrestrial animal in New Guinea after introduced deer. Their evolutionary history is poorly known, but genetic evidence suggests emus are their closest living relatives. The casque, a keratinous head structure, has multiple proposed functions: amplifying deep sounds, visual display (it glows under ultraviolet light), thermal regulation, or dominance disputes. The southern cassowary is the fourth-tallest and third-heaviest living bird. The northern cassowary is the most recently discovered and most threatened species. Despite their dangerous reputation, recorded fatalities are fewer than those from ostriches in South Africa.
Did You Know?
- Cassowaries lack a tongue.
- Their casque glows under ultraviolet light, with different species showing distinct patterns.
- The dwarf cassowary is much smaller than the northern or southern cassowary.
- Cassowaries produce the lowest-frequency bird call known, at the lower limit of human hearing.
Frequently Asked Questions
What is a Cassowary?
Cassowaries are large, flightless ratite birds inhabiting the tropical forests of New Guinea, the Moluccas, and northeastern Australia. Standing roughly 1.5 to 2 meters tall, they lack the keeled sternum that gives flying birds their structural advantage.
Why is Cassowary called the world's most dangerous bird?
Their inner toe claw is long and dagger-shaped, capable of inflicting severe wounds in a defensive kick. That said, the common ostrich actually accounts for more human deaths per year, so the 'most dangerous' label is more cultural than statistical.
How fast can Cassowary run and how long do they live?
A cassowary can sprint through dense undergrowth at roughly 50 km/h (30 mph). In the wild they typically survive 18 to 20 years, while captive individuals have been known to reach around 40.
How many Cassowary species are there?
Three extant species make up the genus Casuarius: the southern cassowary, the northern cassowary, and the dwarf cassowary.
What is special about Cassowary's vocalization?
Cassowaries produce the lowest-frequency bird call documented to date, a deep resonant boom that can travel considerable distance through rainforest.
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