The Double-wattled Cassowary

By Susana Cortázar

Her beauty and grace belie her name – Killer. However, colorful and inquisitive Killer, Zoo Miami’s fetching double-wattled cassowary, true to her species, Casuarius casuarius, is quite an aggressive bird.

In 2005, two cassowary eggs arrived at Zoo Miami from the Denver Zoo. On May 23, one of them hatched, grew and blossomed into our lovely bird.

Native to New Guinea, Australia and The Aru Islands, the magnificent double-wattled cassowary is a ratite – non-flying bird – and is the third largest native animal in Australia after the red kangaroo and emu. Killer, at 158 pounds, is no light-weight. Although difficult to measure because of their posturing and movements, these animals are between 59” – 71” tall, a range within which Killer falls. Their lifespan is 40 – 50 years.

Double-wattled cassowaries are diurnal, solitary animals, with males and females usually only coming together during courtship, breeding and egg-laying season. Once the female lays the eggs, she walks away, while “dad” takes over the job of incubation– approximately seven weeks – and cares for the chicks until they are ready to go off on their own. While dad is busy incubating and baby-sitting, mom is equally as busy breeding with other males and laying more eggs. Both sexes are polygamous.

Photo by T.M. Arnett

When babies hatch, they are brown with dark stripes that start disappearing as they grow, and their sex is unknown. Feathers must be pulled and sent to a special lab for sex determination. The alternative, of course, is to wait until one of them lays an egg.

Photo by T.M. Arnett

Cassowaries are predominantly frugivorous and Killer’s diet consists of papaya, oranges, grapes, apples, shredded carrot, lettuce, and ratite pellets. For enrichment, her keepers at Zoo Miami reward her with mangoes, dwarf schefflera leaves and berries, ficus figs and leaves, and Hong Kong orchid flowers, all of which are found at Zoo Miami and therefore easy to get.

Double-wattled cassowaries have an inefficient digestive system which means they tend to swallow fruits whole – seeds and all – and semi-digest them. They then disperse the fruits and seeds through their excrement, thereby germinating the ground for new trees to grow.

They are very interesting-looking animals – with their vivid aquamarine face, vibrant blue neck, red double-wattle, and modified feathers that look like eyelashes any woman would kill for – but there are a few other features which are instant attention-grabbers. First is the casque - made of keratin - just like nails and hair. Although born casque-less, theories as to why these birds grow this amazing feature on their head range from it being a secondary sexual characteristic to being a tool for pushing aside leaves as they forage, from using it as a weapon during disputes, to augmenting deep sounds. But an agreement as to its purpose has not been reached by experts.

Killer’s ankles and feet are also a most striking characteristic. Thick ankles flow into three-toed feet. Each toe has a nail with the innermost toe brandishing a modified nail about 5” long that looks like a dagger and is used during fights. And yes, it can easily disembowel animal or human with a swift kick.

You want more interesting facts about Killer? Cassowaries have double-shafted feathers, meaning that, unlike other birds, two feathers come out of the same shaft. They also have rudimentary wings with modified feathers that look like quills.

One of Killer’s keepers, Kresimir Golenja, who has been a keeper at Zoo Miami 13 years, explains that because of the nature of these animals, “keepers must practice protected contact. We don’t work directly with her and always have a barrier between us. At Zoo Miami we use a system of gates and pulleys to separate the bird from her keepers.” Although Killer is easy to take care of, the most important part of working with her is “protecting ourselves from her,” says Golenja.

Ratites are not exactly known for their “brain power,” explains Golenja, but “are certainly trainable.” What about Killer? “She’s somewhat trained. She underwent operant conditioning and quickly learned to step on the scale in order to be weighed,” he adds.

And who came up with her name? “Well,” says Golenja, “when she was a chick, there was a debate among keepers whether to name her Shnookums or Killer. Because they are such aggressive birds, Killer prevailed.”

Next time you visit Zoo Miami, make sure you pay Killer a visit. She will be very excited to see you and will walk up to the fence for an up-close peek at you. Just please don’t stick your finger in her cage!

Photo by Ron Magill