Recognition of individual large mammals by natural features is an ancient practice, the usefulness of which has recently become appreciated in field studies. We show that such recognition is possible and repeatable, under particular circumstances, with macropodid marsupials in the field in Australia. In trials, there was a 98% agreement between observers in identification of individuals of both eastern grey kangaroos Macropus giganteus and red-necked wallabies M. rufogriseus. Characters used to identify individuals were first definitive ('oddity') characters, and then specific sets of character-states. However, in time observers came to recognise individuals 'on sight', by unconscious summation of character-states. Recognition skills could be readily learned by observers, allowing almost complete populations of these species to be known and the component members studied individually. The technique should be applicable in studies of other macropodid populations.
