Wednesday, 
May 16, 2018

The Casque

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Looming well over five feet tall, with shimmering jet-black feathers, vibrant head and neck skin that rivals a painter’s palette, and a dramatic helmet-like casque atop its head, the southern cassowary would not seem out of place in the Jurassic Period. Though flightless, this ancient species sports other ninja-like moves when needed: debilitating kicks with long legs armed with dagger-like claws; sprinting up to 30 miles per hour; ability to spring 5 feet in the air from a standstill; and a swimmer’s pace worthy of the Olympic Games. A quick internet search of “cassowary claw” will leave little doubt about how these birds protect their young and defend themselves (and land on “most dangerous birds” lists). Normally they are shy and reclusive, but once they are riled up, you’d best “Be Cass-o-wary” (as local Australian signs advise) and get out of the way! Sometimes described as looking like a cross between a dinosaur and a turkey, the southern cassowary is the second heaviest bird in the world, with females, which are larger than males, reaching 165 pounds. Only the ostrich has more avian heft. [caption id="attachment_125401" align="aligncenter" width="2000"] THE RIGHT RATITE
(From left): Southern: Also called the double-wattled cassowary, this is the only type that lives beyond Papua New Guinea; Northern: The single-wattled cassowary is the most threatened of the three species; Dwarf: This cassowary lives at higher elevations than its larger ratite cousins.[/caption]
How much a female southern cassowary can weigh (in pounds)

Who Is Who?

Cassowaries are part of the “ratite” group of birds, along with the emu of Australia, the kiwi of New Zealand, the ostrich of Africa, and the rhea of South America. These large, flightless birds are well-adapted for running instead of flying like eagles or swimming like penguins. The three cassowary species come in three different sizes: the southern or double-wattled cassowary Casuarius casuarius is the largest and the only one to persist beyond Papua New Guinea—it is the only cassowary species found on mainland Australia, inhabiting northern Queensland. This species is part of the new Walkabout Australia at the Safari Park. The northern, or single-wattled cassowary C. unappendiculatus, a bit smaller than the southern variety, is the most recent to be discovered by scientists (in 1860), and is likely the most threatened of the three species. Its flamboyant skin color may change with its mood. The smallest variety is aptly called the dwarf cassowary C. bennetti. While it may be the most colorful cassowary, it lacks those eye-catching wattles. Its casque is black and triangular in shape and flattened at the back. It inhabits higher elevations of New Guinea, leaving the lowland rain forests to its larger cousins; the three cassowary species do not overlap and occur in low population densities.
Normal cassowary life span in zoos (in years)

Blade Runner

There is much discussion about what exactly the cassowary’s wedge-shaped helmet adornment is for. The casque, which starts to develop at one to two years of age, is made of tough, elastic, spongy material covered in keratin, like a tortoise shell or horse hoof. Some say the blade-shaped accessory serves as a streamlining shock absorber that protects the bird’s noggin as it bolts through the rain forest underbrush, while others say it reveals the bird’s age or dominance. Another theory is that it helps project the birds’ deep, booming calls through the dense forest; cassowaries are solitary by nature, so hearing another bird’s call is an important heads-up for a potential mate or a “get off my lawn” cue. Still others insist the casque attracts mates—both males and females have them—but keepers have noted that even birds with “crummy casques” are perfectly attractive to mates. [caption id="attachment_125402" align="aligncenter" width="2000"] DOTING DAD
Males guard and raise their chicks for several months, until they are large enough to fend for themselves. Below: The powerful three-toed feet of a cassowary are equipped with a formidable, four-inch, razor-sharp claw on each inner toe. (Credit: Dave Watts / Alamy Stock Photo)[/caption]
Number of days the male cassowary incubates the eggs

Green Eggs and Dad

Southern cassowaries spend most of their life as solo acts, likely due to the vast amounts of fruits, berries, and other tasty foods they must rustle from the forest floor (11 pounds a day, by some estimates). Females manage a home range three to six times larger than that of males, which overlaps with several potential mates. Through a complex breeding system, females select a male to breed with, then stick around just long enough to lay 3 to 8 green eggs (3 to 7 days apart), which the male dutifully guards and incubates for about 50 days in a simple indentation nest on the forest floor. Once the brown, striped chicks hatch, he will protect them from predators and teach them the cassowary “ropes” for about nine months, at which time the youngsters will be large enough to fend for—and defend—themselves. Females mate with up to three males; males with chicks will drive off females, which have been reported to kill the youngsters.
Species of cassowary

Foods and Feces

Cassowaries scour worn trails snaking through forests in search of food and water resources. They seek a diverse diet, with southern and dwarf cassowaries indulging in fungi, snails, insects, fish, frogs, rodents, and even carrion, as well many types of fallen fruit. As critical seed dispersers in tropical forests, cassowaries are considered keystone species. They fill a similar ecological niche to large-bodied, fruit-eating mammals in other rain forest habitats. Since these birds gulp the fruits of their labor down whole, with a toss of the head, and they have a relatively short digestive tract, their feces are large and colorful, and give many seeds a leg up on sprouting. [caption id="attachment_125526" align="aligncenter" width="2000"] BIRD ON BEACH!
In Australia, cassowaries occasionally emerge from the forest onto a sandy beach, giving sun bathers quite a surprise. (Credit: iStock.com/bendenhartog)[/caption]

Stranger Danger

Sometimes a southern cassowary will find its way out of the dim rain forest onto a beach—especially Australia’s Mission Beach—where it saunters about, scattering startled sunbathers. If harassed by domestic dogs, the big birds have been known to flee into the ocean! Cassowaries have been somewhat demonized, perhaps due to their intimidating stature and energetic weaponry. They are regularly at the top of dangerous bird lists, though truth be told, they prefer “flight” to fight. According to National Geographic, the last recorded fatal human-cassowary encounter was in 1926, and that was in self-defense—teenagers were hunting the birds and when one boy fell, a cassowary leaped on top of him and (accidentally?) slashed his jugular vein. More recently, in 2012, a tourist in Queensland, Australia was kicked by a cassowary and tumbled off a ledge into a body of water. He was unharmed. That kind of track record really shouldn’t foster animosity toward this big, bold, beautiful bird. You can “wattle” over to the new Walkabout Australia at the Safari Park and see for yourself.