How many cassowaries are there in the Wet Tropics?

Cassowary, Photo: Campbell Clarke

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.

Management implications

Cassowary juvenile, Photo: Campbell Clarke

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

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.

Reference: Westcott, D., Metcalfe, S., Jones, D., Bradford, M., McKeown, A., Ford, A. (2014) Estimation of the population size and distribution of the southern cassowary, Casuarius casuarius, in the Wet Tropics Region of Australia Project © CSIRO

Advertisements