Use of Rock-wallaby Faecal Pellets for Detecting and Monitoring Populations and Examining Habitat Use.

Abstract

Counts of faecal pellets are commonly used to measure dispersion of medium to large, herbivorous mammals, including macropods. Rock-wallabies, Genus Petrogale, are relatively difficult to observe in the daytime, so indirect techniques for survey and measurement of dispersion and population size are attractive. Faecal pellets of rock-wallabies are easy to identify and to detect, often being rapidly dried and well preserved on rock substrates. Pellets have been used in surveys to detect past and recent presence of rock-wallabies in refuge habitat. Their measured distribution can also indicate limits to foraging range away from refuge habitat, information that is important for their management. By making careful correction for the expected form of distribution of rock-wallaby foraging away from refuge habitat, pellet sampling can be used to measure their habitat preferences. Pellet sampling can be used, with careful survey design, to monitor change in colony size over time; but it could be used only with difficulty to indicate absolute population size accurately. In some circumstances it will be more efficient to attempt to observe and count the wallabies directly.