In breaking – even heartbreaking – news, recently released data reveals that far from the already worryingly low number of an estimated 1,000 cassowaries left in Australia, this figure may have been overestimated by six times the real number because of small survey areas.

Previous research had been used to estimate that around 1200 southern cassowaries were left in the Wet Tropics of Australia (down from 4,000 in 1988). But a recent study by local researcher Les Moore* suggests that population estimates of cassowaries in Mission Beach and other surveys may have been overestimated by six times the real figure.

Using results of an intensive field survey, approximately 102 km2 of rainforest was surveyed and a total of only 110 cassowaries was identified, 49 of which were adults. This is approximately 35% of the adult population previously estimated for the Mission Beach area.

It was concluded that the previous practice of surveying small areas at Mission Beach had led to a consistent overestimation of the cassowary population.

Rainforest Rescue’s Community Conservation Project Officer, Chris Bennett said:
“The figure could now be significantly less than that [the previous estimate of 1200], putting the species much more under threat than was realised and heightening the need for greater protection for their habitats.”

The cassowary is not just an extraordinary and delightful creature for humans to enjoy observing: it is considered a “keystone” species of the rainforests, central to the integrity of their delicate ecological balance. Because they are the only bird in the region capable of swallowing the large fruits whole – and later voiding the seeds completely, often with flesh still adhering – this gentle treatment makes the bird an efficient disperser of fleshy-fruited seeds. This, in turn, means that over 100 native rainforest plants are dependent on the cassowary for regeneration, and thus the whole web of life that is supported by these plants.

The dramatically downward estimation of the numbers of this wonderful bird – embraced by Rainforest Rescue as their flagship for conservation – has heightened the urgency of the Daintree Buy Back and Protect Forever Project. The home ranges of about half the cassowaries in the area are intersected by roads – with all the associated impacts of traffic, dogs and loss of corridors. “These areas should be protected and Rainforest Rescue has purchased several properties to help retain corridors, but there is a need for much more to be done,” said Chris Bennett.

Please make a donation to help buy back the Daintree rainforest as habitat for the endangered cassowary.

*Moore, L.A., Population ecology of the southern cassowary Casuarius casuarius johnsonii, Mission Beach North Qld, 2007

By Sue Vader.