Water Balance in the Mulgara (Dasycercus Cristicauda), A Carnivorous Desert Marsupial

Abstract

A small Australian marsupial, the mulgara or crest-tailed marsupial-mouse (Dasycercu8 cristicauda Krefft), lives on a predominantly or exclusively carnivorous diet. It, inhabits the most arid part of central Australia where the average rainfall is 5-10 in. per year. In the laboratory and in the absence of heat stress, the animal can maintain or gain weight without drinking water on a diet of whole mice or fresh lean meat. Its kidney can produce a urine highly concentrated with respect to urea, and the large amounts of urea formed on a carnivorous diet can therefore be excreted in a relatively small volume of urine. This desert animal can therefore subsist on the water contained in its food without drinking free water or eating succulent plant material.