NATURE: Cracking The Koala Code

Loud bellows ring out from a small pocket of forest surrounded by dense suburbs and busy roads in Brisbane, Australia. It’s mating season for koalas. Their thunderous roars are difficult to reconcile with the familiar perception of them as cuddly creatures.

But it turns out their world is in fact far from cute and cuddly. Rather it is filled with social pressure, conflict, disease, overcrowding and the external stresses of living in the middle of what amounts to an alien world.

Predominantly slow-moving, energy-conserving koalas are not exactly well-equipped to handle speeding traffic and packs of dogs, or the consequences of encroaching urbanization. For a real change of pace, NATURE enters the world of urban koalas trying to adapt to life in the fast lane.

"Cracking The Koala Code" explores the day-to-day dramas of a number of urban koalas, seen through the eyes of the scientists studying their every move and vocalization.

Fascinating social dynamics include territorial displays, vicious fights, and the surprising mating strategies of traveling male koalas, rogues who truly play the field. New science even “cracks the koala communication code,” providing insights into their basic language and social structure.

“People love koalas, yet there is a great deal about them they would find surprising,” said Fred Kaufman, series executive producer and recently named recipient of International Wildlife Film Festival’s Lifetime Achievement Award. “Koalas may seem docile and sweet, but they are really quite active and can be very aggressive and loud. Viewers will get a whole new perspective after watching this film.”

Biologists Cathryn Dexter and David Black have been studying koalas in the Brisbane suburb of Petrie in an effort to understand the social interactions within an urban koala colony.

They have been tracking the movements of more than 70 koalas, monitoring their health, providing medical assistance when necessary, and compiling data they hope will be useful in creating safe passageways through high traffic areas for the animals.

Elsewhere in Queensland, biologists Bill Ellis and Sean Fitzgibbon are engaged in research sponsored by the San Diego Zoo to learn more about the koala social system, mating habits and communication.

Using 3G solar-powered mobile phones to record female koala vocalizations, and using those recordings in the field to evoke male koala responses, they have managed to decipher some of the koalas’ communications.

Their studies suggest that female koalas may be able to tell which males are bigger, and therefore more attractive, by their bellows alone.

Through DNA analysis, the team also made a most surprising discovery – that traveling males sire about 40 percent of the offspring in koala groups, despite the best efforts of the group’s resident dominant male.

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