Low-density koala (Phascolarctos cinereus) populations in the mulgalands of south-west Queensland. I. Faecal pellet sampling protocol
B.J. Sullivan1,2, G.S. Baxter1, and A.T. Lisle3
1School of Natural and Rural Systems Management, The University of Queensland, Gatton, QLD 4343, Australia
2Present Address: South-west Atlantic Seabirds at Sea Team, Falklands Conservation, Jetty Centre, Stanley, Falkland Islands
3School of Agronomy and Horticulture, The University of Queensland, Gatton, QLD 4343, Australia
Koala (Phascolarctos cinereus) populations in eastern Australia are threatened by land clearly for agricultural and urban development. At the same time, conservation efforts are hindered by a dearth of information about inland populations. Faecal deposits offer a source of information that is readily available and easily collected non-invasively. We detail a faecal pellet sampling protocol that was developed for use in a large rangeland biogeographic region. The method samples trees in belt transects, uses a thorough search at the tree base to quickly identify trees with koala pellets under them, then estimates the abundance of faecal pellets under those trees using 1-m2 quadrants.
There was a strong linear relationship between these estimates and a complete enumeration of pellet abundance under the same trees. We evaluated the accuracy of our method in detecting trees where pellets were present by means of a misclassification index that was weighed more heavily for missed trees that had high numbers of pellets under them. This showed acceptable accuracy in all landforms except riverine, where some trees with large numbers of pellets were missed. Here, accuracy in detecting pellet presenced was improved by sampling with quadrants, rather than basal searches. Finally, we deceloped a method to reliably age pellets and demonstrate how this protocol could be used with the faecal-standing-crop method to derive a regional estimate of absolute koala abundance.