Abstract
Kangaroos at Wallaby Creek lived with the persistent presence of dingoes in the valley, there being no place, time of year or of day when kangaroos could be free of risk. An adult kangaroo might encounter dingoes a few hundred times in its life. Dingoes appeared not to be selective for the sizes of groups of kangaroos that they contacted. Large adult males and females with medium pouch young were overrepresented in the samples of kangaroos contacted by dingoes. No kangaroos ignored the detected presence of dingoes; all became alert, and most fled. The distances at which they became alert to a dingo group depended upon the kangaroo group's size, larger groups never being surprised by dingoes at short range as were some smaller groups. On average larger groups fled when the dingoes were further away. Among classes of kangaroos, large adult males fled least far, and tended to react to dingoes less strongly (in terms of alertness or flight) than other classes. They also exhibited two forms of defence, taking to water when pursued and warding off attack, that other classes did not show.