AG40 Australian GeographicLiving on a rainforest-clad property in prime cassowary habitat near
Mission Beach, conservationist Ingrid Marker has seen fi rsthand the grisly
results of many wild dog–cassowary interactions.T
HE FUNCTION OF a cassowary’s casque –
its head crest – has long been debated.
Until recently, it was thought to help the birds
determine the direction of sounds, such as deep
vocalisations from distant cassowaries or
rainforest fruits crashing to the ground.
However, new findings, published in
Scientific Reports in January 2019,
suggest it acts as a kind of radiator,
enabling the birds to shed heat
more efficiently. “Just as humans
sweat and dogs pant in hot
weather or following exercise,
cassowaries offload heat from
their casque,” says study author
Danielle Eastick of La Trobe
University in Melbourne.Keeping cool
The cassowary’s casque starts developing aft er
from the age of about 12 months. It’s made of
a spongy material surrounded by a hard keratin. layer.ILLUSTRATION: KEVIN STEADSome of the biggest threats here are climate change, uncontrolled
bushfires, feral cattle and pigs. “Feral cattle spoil waterholes and
we know that cassowaries need water to cool down in the top
of the dry season,” Tim says.F
URTHER SOUTH, in the Wet Tropics, the conservation
challenges are different. Here the birds are killed in sig-
nificant numbers by vehicle strikes and dog attacks. Ingrid
says that in the past two years alone, she has responded to
18 repor t s of ca ssowa r ies m au led by dog s a round M ission Beach.
She’s often unable to recover a body, so the true scale of the
problem doesn’t figure in official statistics. There’s a culture, she
says, of owning aggressive dogs for hunting feral pigs and “putting
them in your ute to go running around on a Friday and Saturday
night is a huge recreational pastime”. Dogs are sometimes let
loose in cassowary habitat, although it’s illegal, and “any animal
that happens to get in their path is often preyed upon”.
However, most adult cassowaries that come into care at the
rehabilitation centre, which can house up to 18 birds, have been
hit by cars. If one is struck at 50km/h it has a good chance of
surviving, Ingrid says. But those hit by cars doing 100km/h have
almost no chance. Juveniles and chicks orphaned through dog
attacks, some just 2–3 days old, are also commonly admitted.
The last time the facility was inundated with injured and
sick birds was following Cyclone Yasi in 2011.
“There wasn’t a leaf on a tree, and if the cassowaries survived
the falling of the debris then they were subjected to starvation,”
Ingrid says.
“In a natural situation, they could have walked from the
coast up into the mountains, where there’s still plenty of fruit
around, but in the fragmented landscape in which they now
live they can’t move across country.”Most of the centre’s birds are released once they’re healthy.
Because of habitat fragmentation, carers are cautious about
release locations. These need ample food and water and no other
cassowaries, because they’re solitary animals and very territorial.
Local traditional owners and the scientists are often consulted.
At the centre, human contact with the birds is minimised.
Young cassowaries are fed a wide variety of fruits, hidden in
their enclosures to make them challenging to find. Carers hope
the bird s’ inst inct ive behav iour s w i l l be st rong enoug h for them
to forage successf u l ly once relea sed. “In rea l it y, they aren’t going
to be as comfortable in the wild or as knowledgeable as a wild
bird,” David says. “So they’re always going to be at a bit of a
disadvantage, and we don’t have a good understanding of how
well they do after release.”I
NGRID SAYS ONE reason cassowaries get hit by cars is they’re
in no hurry to get off the road. “People think they are stu-
pid,” she says. “[But] what they are is arrogant. They are the
queens of the jungle and don’t move out of the way for anybody.”
Females are particularly assertive and territorial, Wren says.
She once climbed a tree, heart pounding, to escape one intim-
idating her. These intelligent birds are highly attuned to any-
thing going on within their realm, she adds, telling the story
of being slowly escorted out of a cassowary’s territory during
survey work: “I was walking along a river and she was walking
behind the vegetation, 10m behind me, calling regularly. When
I crossed the river, she came out of the foliage and stood there
staring at me for ages.”
David says peacefully observing a cassowary at a distance as
it goes about its daily activities is a wonderful experience: “A
bird has tolerated my presence for hours on end on a few occa-
sions and it’s always a really peaceful and privileged feeling.”Most adult cassowaries that come
into care at the rehabilitation centre
have been hit by cars.