The Wet Tropics is home to about 4,400 cassowaries, with a minimum of five percent being the year’s youngsters. The figure is based on several years of monitoring and DNA analysis by Dr David Westcott and his team of researchers at CSIRO under the National Environmental Research Program.
Their Wet Tropics surveys covered 1886 kilometres and 156 transects. They recorded 1444 cassowary signs (dung, feathers, tracks and sightings). They also did 170 surveys of focus sites and recorded 296 signs of cassowaries. The DNA of 435 sub-samples was analysed from 134 different dung samples.
What do the population numbers mean for cassowary conservation?
The population estimate is consistent with the upper range of previous estimates undertaken 20 years ago.
While these cassowary population numbers are larger than have been often quoted, they are still small enough to place the cassowary at risk from chance events such as cyclones, genetic effects, and increasingly fragmented habitat.
The conservation status of the cassowary remains endangered and populations are likely to decrease if habitat fragmentation worsens and cyclones become more intense or more frequent with climate change.
Future investment in cassowary management should focus on cassowary habitat protection and connectivity.
A regular cassowary monitoring program (for local focus sites and the Wet Tropics region) is essential to track population trends and life histories.
Cassowary monitoring with Traditional Owners in Cape York should be established to survey the increasingly fragmented populations in areas such as the McIlwraith Range.
Project 3.4 Final Report – Estimation of the population size and distribution of the southern cassowary, Casuarius casuarius, in the Wet Tropics Region of Australia
You can download the full report above or visit the NERP website for more information.
The article discusses the evolution of the various cassowary species and the anatomy of the cassowary casque and how it may be used. It emphasises that we still have a lot to learn about all these facets of cassowary research.
You can also download a copy of the research below:
The Australian Veterinary Journal has published a paper on successful methods for cassowary immobilisation, restraint, transport and satellite tracking. The paper outlines the use of anaesthetics for safe handling of adult and juvenile cassowaries taken into captivity and released back into the wild.
The paper also details safe ways to transport cassowaries and to attach satellite trackers to monitor their movements after release back into their natural environment. Monitoring indicates that the released cassowaries suffered no behavioural ill-effects from the chemical immobilisation, restraint or transport.
The cross marks the spot for needle entry for the anaesthetic.
This is one of the first studies to use satellite telemetry to monitor the movements of a free-ranging large ratite. Future monitoring of released cassowaries can help to tell us a lot about their movements and behaviour. Longer term satellite studies are required to assess if the birds successfully locate and establish a home range and develop into breeding adults.
The authors of the study are Hamish Campbell (UNE), Ross Dwyer (UQ), Scott Sullivan (QPWS), Dan Mead (QPWS) and Graham Lauridsen (Tropical Vet Services, Tully).
Cassowary Sightings from the Cassowary Coast 1999-2012
For many years, CRT member C4 have been collecting sightings information about cassowaries through a daily log at their Visitor Centre in Mission Beach.
When local retiree, Jeff Larson (a self-confessed “mad stats” person), joined C4 in 2009, he generously volunteered his time to enter all the data into a spreadsheet for public viewing. Continue reading →
Young cassowary chicks have a low chance of survival after the premature death of a parent, so chicks are regularly brought into care at the Garner’s Beach rehabilitation facility where they are hand-reared by DERM staff until ready for release into the wild.
Until recently, nothing was known about the fate of the released birds, but a new research project is changing that. Continue reading →
Road mortality is the greatest cause of known cassowary deaths at Mission Beach. Between 1992 and June 2010, at least 60 cassowaries died on local roads. At the request of Terrain NRM, James Cook University (JCU) undertook significant research into traffic impacts on cassowaries (and other fauna) on Mission Beach roads. Continue reading →