Our last modern bird for Birthday Week is the Cassowary! The Cassowary is a Palaeognath, so one of the two major divisions of modern birds, featuring Ratites (such as the Cassowary, and the Ostrich) as well as animals such as the Tinamous. The Cassowary has three extant species and one extinct, and it has existed for about 5 million years. It evolved some time in the Early Pliocene, in the Zanclean age, in the Neogene. Fossil evidence of the Cassowary is known from Papa New Guinea and Australia, though it might be from another ratite – it’s difficult to tell. The one definite extinct species, C. lydekkeri, is known as the Pygmy Cassowary. It lived during the Pleistocene, in New South Wales and Papua New Guinea, and probably went extinct due to the climate change occurring at the time (as humans weren’t extremely common in that region yet.)
Northern Cassowary, by Viajar, CC BY 2.0
The Cassowary lives today in New Guinea and Australia, living in deep forests of these regions, especially rainforests, though they do go into the grasslands and swamp forests. They are omnivorous birds, eating on fruits, shoots, grass, as well as fungi, invertebrates, and small animals. They are well known in circles for their propensity to violence – when startled they are capable of killing human beings with their powerful kicks, leading to frequent comparisons with their cousins, the extinct Dromaeosaurs. However, they are also very shy animals, not very willing to approach humans, and oftentimes fatal injuries to humans (and dogs) are due to humans feeding the birds or keeping them in captivity in non-conservationist manners (ie, as pets, rather than in zoos) – both inappropriate situations which, ultimately, should be blamed on the humans, not the birds.
Dwarf Cassowary, by Nick Hobgood, CC BY-SA 3.0
The three species of the Cassowary are similar, but easily distinguished from one another. The females are bigger and more brightly colored, and they do not have tail feathers – in fact, their wings are small and reduced, and their wing feathers are more like porcupine quills than feathers. Their wedge shaped, fluffy bodies probably aid the birds in going through the thorny, vine-filled rainforest. They have three toed feet with sharp claws reminiscent of non-avian theropods. They have large crests, or casques, on their heads that grow with age, and their shapes and sizes are dependent on the species. They are probably used for sexual display, though their exact function is under debate.
Southern Cassowary, by Scott Hamlin, CC BY-SA 2.0
They are solitary birds, except during courtship and egg-rearing. Bonded pairs have territories of about 7 square km, and lone females have overlapping territories of several males. Females move across male territories, though staying in the same general area, mating with the same males during their life. Females will make vibratory sounds to attract males, who run towards the females with their necks parallel to the ground, moving their heads dramatically. The female approaches the male, and the male will crouch on the ground in response. The female will step on the male’s back briefly, before crouching next to him to mate or attacking him – if it’s the latter, the female will chase the male into bodies of water. The male then dives into the water and submerges upt to the neck and head, and the female chases the male until the male brings her to the shallows. They then mate after the female moves her head and crouches, often for long periods of time.
Northern Cassowary, by Quartl, CC BY-SA 3.0
Cassowaries mate from May to June, and females lay three to eight large eggs, that are only smaller than Ostrich and Emu eggs. The male incubates the eggs for 50 to 52 days, and then defends the chicks for another nine months. Young males leave to find territories. Females don’t care for the young, but rather keep laying eggs with other males. The babies have brown stripes and light brown bodies, and are often – unfortunately – stolen as pets by locals. They then grow darker as they age, until getting the coloration of the adults.
Adult male Southern Cassowary with chicks, by Arjan Haverkamp, CC BY 2.0
The Southern Cassowary is the best known species, and the most famous. It lives in Papa New Guinea, Seram, the Aru Islands, and Northeastern Australia. It is a Vulnerable animal, due to habitat loss and an already limited range. It is listed as Endangered under Australian conservation legislation. Feral animals eat their eggs, and hunting and roadkill also lead to the population declining – with hunting and feral animals being the worst threats. It’s estimated that there are between 10,000 and 20,000 of these birds in the world, with between 1,500 and 2,500 in Australia. They are, however, bred in captivity in the United States. They make booming calls during mating season, and the chicks will make high-pitched whistles. They have stiff, bristle-like black feathers, a blue face and neck, red on its neck and two red wattles that hang down low from the throat. Their casque is brown and tall, and the females have long casque and larger bills, as well as brighter colors. In size, they weigh about 85 kg, and are about 190 cm tall – and it is the largest living Asian bird.
Northern Cassowary, By Viajar, CC BY 2.0
The Northern Cassowary lives only in Papa New Guinea, Yapen, Batanta, and Salwati. They live at low elevations, and there are only about 2,500 to 10,000 in the world. Due to habitat loss and excessive hunting, it is also declining, and is listed as Vulnerable. Like the Southern Cassowary, it has stiff black body feathers and blue facial skin, though its neck is bright red and yellow, and it has a single reddish-orange wattle. It is similar in size to the Southern Cassowary, though slightly smaller, about 180 cm tall, and weighing at most 58 kg. It lives in coastal swamps and lowland rainforests, and it is also shy and solitary.
Dwarf Cassowary, by Gaurav Nalkur, CC BY-SA 3.0
The Dwarf Cassowary is the smallest living member of the genus, only at most 26 kg in weight. Still, it is a very large bird, with the same black, stiff body feathers. It has blue skin on its neck, pink cheeks, and a dark head, as well as a low triangular casque. Females are brighter in their skin and larger, as well as with longer casques. They live in New Guinea, New Britain, and Yapen Island, and is a solitary bird like other members of the genus. It is not considered threatened, and is stated as Least Concern as populations appear to be stable, despite habitat loss.
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