Tuesday, May 28, 2013

C is for CASSOWARY


The name cassowary comes from two Papuan words 'kasu' meaning horned and 'weri' meaning head, referring to the prominent casque on its head.  An adult cassowary can stand up to 1.8 metres (6') tall and the average weight is 38kg (84 lb) for males and 47kg (104 lb) for females.


The cassowaries are ratites, very large flightless birds, in the genus Casuarius native to the tropical forests of New Guinea, nearby islands and northern eastern Australia.  There are three extant species recognised today; the most common of these, the Southern Cassowary, is the third tallest and second heaviest living bird smaller only than the ostrich and emu.  Cassowaries mainly feed on fruit, although all species are truly omnivorous and will take a range of other plant food including shots, grass seeds, and fungi in addition to invertebrates and small vertebrates.  They are very shy, but when provoked they are capable of inflicting injuries to dogs and people, although fatalities are extremely rare.

Cassowaries have three-toed feet with sharp claws.  The second toe, the inner one in the medial position, sports a dagger-like claw that is 125mm (5 in) long. This claw is particularly fearsome since cassowaries sometimes kick humans and animals with their enormously powerful legs.  They can run up to50 km/h (31/mph) through the dense forest.  They can jump up to 1.5 m (4.9ft) and they are good swimmers, crossing wide rivers and swimming in the sea as well.

Cassowaries are solitary birds except during courtship, egg-laying and sometimes around ample food supplies.  The male cassowary defends a territory of about 7 square kilometres (1,700 acres) for itself and its mate, while females have overlapping territories of several males.  While females move between satellite territories of different males, they appear to remain within the same territories for most of their lives, mating with the same or closely related males over the course of their life span.  Courtship and pair bonding rituals begin with the vibratory sounds broadcast by females.  Males approach and run with necks parallel to the ground with dramatic movements of the head, which accentuate the front neck region.

The female approaches, drumming slowly.  The male will crouch upon the ground and the female will either step on the male's back for a moment before crouching beside him in preparation for copulation or she may attack.  This is often the case with the females pursuing the males in ritualistic chasing behaviours that generally culminate in water.  The male cassowary dives into the water and submerges himself up to his upper neck and head.  The female pursues him into the water where he eventually drives her to the shallows where she crouches making ritualistic motions of her head.  Males are far more tolerant of one another than females, which do not tolerate the presence of other females.


The breeding season starts in May or June.  Females lay three to eight large, dark bright green or pale green-blue eggs in each clutch in a prepared heap of leaf litter.  Only ostrich and emu eggs are larger than those of the cassowary.  The female does not care for the eggs or the chicks but moves on to lay eggs in the nests of several other males.  The male incubates the eggs for 50-52 days, removing or adding litter to regulate the temperature, then protects the brown-striped chicks, who stay in the nest for about nine months, defending them fiercely against all potential predators, including humans.  The young males then go off to find a territory of their own.  Young cassowaries are brown and have buffy stripes.

The cassowary is Australia's largest land animal and plays a unique role in the ecology of the World Heritage listed rainforests of tropical Australia.  Both the Australian Government's Environment Protestion and Biodiversity Conservation Act 1999 and the State of Queensland's Nature Conservation (Wildlife) Regulation 1994 list the Southern Cassowary as an endangered species.    These guardians of the rainforest are still threatened by habitat loss, road deaths and attacks by dogs.  More than 80% of its prime habitat, coastal lowland rainforest, has been cleared over the last 100 years.  Nearly a quarter of the remaining cassowary habitat has poor conservation protection.  Links between the remaining patches of rainforest are essential if the cassowary is to survive.  Scientists believe only 1200-1500 cassowaries survive in the wild of Australia; this is comparable with the number of Giant Pandas in China.

Cassowaries are a keystone species which means they are vital for seed dispersal in the rainforest.  Over 150 rainforest plants rely on them, especially for dispersing the seeds of large-fruit species.  The ecology and extensive distribution of the cassowary makes it an effective conservation 'flagship' species whose conservation will have significant flow on benefits for many other species and ecosystems.


Some beautiful aboriginal art depicting cassowaries and their chicks.

This is an interesting item I found while researching the cassowary:


The cassowary is native to New Guinea and Australia and not found anywhere in North Borneo so why would this flightless bird be chosen for North Borneo stamps instead of other birds?  The answer is, it's a mistake in design?  According to L. Shipman's "Postal History of North Borneo (part 3)" the bird intended was a megapode (Megapodius freycinet) and not the cassowary.  (that sounds as though the megapode has a French flavour...'freycinet" although I could be wrong).

P.S.  Australians may wonder why I didn't include corella under "C" but I am thinking seriously of doing a separate type of post for our beautiful parrots.  Is that a good idea do you think?

4 comments:

  1. I loved finding out that it is the female cassowaries that are territorial. How unusual. I wonder whether that is true of any other birds.
    They are striking looking birds (kung-fu experts of the bird world), and the young are so very cute.

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  2. There was a documentary on television several years ago about the cassowary. They are very interesting birds indeed. It would be good to try and find out if other female birds are territorial like this species. I thought the chicks truly gorgeous and was intrigued by the story about the wrong bird being depicted on the North Borneo stamp.

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  3. I have always wondered how a flightless animal can be called a bird..but..there you have it. Love the little striped babies and looking forward to a colourful parrot post.

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  4. I guess it's 'cos they do have wings of some sort but not strong enough to give them flight. Another of nature's conundrums!! I will probably finish this series of birds and then concentrate on parrots as there are so many of them and it will be difficult to decide which to include and which to leave out.

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