Cassowaries are large, flightless birds that are related to emus and found only in Australia and New Guinea (2). The southern cassowary (Casuarius casuarius) has glossy black plumage and a bright blue neck, with red colouring at the nape(3). Two wattles of bare, red coloured skin hang down from the throat. Cassowaries have stout, powerful legs and long feet with 3 toes; the inner toe on each foot has a sharp claw that can reach up to 80 millimetres in length (4).
The name cassowary comes from a Papuan name meaning ‘horned head’, referring to the helmet of tough skin borne on the crown of the head. This helmet (or casque) slopes backwards and is used to push through vegetation as the cassowary runs through the rainforest with its head down. It also reflects age and dominance. The sexes are similar in appearance, although females tend to be larger and heavier. Chicks are striped black and cream, fading to brown after around five months. The adult colouring and casque begin to develop between two and four years of age (4).
Cassowaries are usually solitary, and males are subordinate to females if they meet. Females may lay several clutches of eggs during the breeding season, which runs from June to October. These are laid directly onto the forest floor and the male then takes sole responsibility for their care. The male incubates the eggs for around 50 days, turning the eggs and only leaving his charges in order to drink. He cares for his offspring for up to 16 months, protecting them under his tail if threatened (4).
Cassowaries fight by kicking out with their legs. They have a fearsome reputation, but their diet is composed almost entirely of fruit. These birds are important dispersers of a number of rainforest seeds, ranging far in search of fruiting trees (4).
The destruction of rainforest and wet tropical coastal lowland habitat is the most important cause of the decline in the southern cassowary population. As forest is cleared to make way for agriculture or development, populations become fragmented and isolated, reducing genetic variation. The birds may also not have access to sufficient food or water sources in forest patches. Traffic accidents are also important causes of mortality, particularly in Queensland, where some areas are becoming increasingly populated by humans. Where cassowaries come into contact with humans, dogs pose a threat to their survival, preying particularly on young birds. In New Guinea, cassowaries are important food sources for some communities and are heavily hunted as a result (5).
In Australia, most of the remaining habitat of the southern cassowary is now located within protected areas (3). A recovery plan for the species has been drawn up by the Queensland Parks and Wildlife Service, with the aim of securing and enhancing the status of the southern cassowary in Australia through integrated conservation initiatives (5). In New Guinea, further data on population numbers is required and hunting restrictions may need to be imposed (3). This awesome bird belongs to an ancient lineage and is one of the most striking of the flightless birds; its conservation therefore has important cultural and ecological significance.
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