Essentially nothing is known about the biology and behaviour of the Andean cat (2) (2). Its range is so remote and inhospitable it has proved extremely difficult to survey the area and there are no Andean cats known to be in captivity (2). Knowledge is built up from rare sightings of the animal, physiological studies of stuffed specimens and more recently genetic analysis of faeces (2) (6). The Andean cat's range does appear to coincide with the distribution of the mountain chinchillas (Chinchilla lanigera) and viscachas (Lagidium spp.), and it has been observed hunting these species (2). Both prey species escape from predators by bounding off rock faces and making unpredictable changes in direction. The Andean cat's long tail probably aids in balance when chasing these rodents (2). The Andean cat's diet may or may not include other species, such as birds, reptiles and other small rodents, but there is no information on this (2). This small cat has an acute sense of hearing, which may assist in hunting, due to its well developed ear drums (5). This adaptation is typical of animals that inhabit arid environments with little cover for protection, such as the mountain chinchilla species (2). The Andean cat may suffer from competition with the pampas cat (Leopardus colocolo) for food and space. The pampas cat occurs in higher numbers in the Andes, and also occupies the lower, more productive regions of the Andes, which may constrain the Andean cat (6). The Andean cat has a significantly lower population than the pampas cat and is believed to live in low densities, though no figures are known (5) (6). It appears to be extremely specialised in its habitat requirements, and the presence of rocky piles and boulders may be important (2).