Energy and water metabolism of the Kowari, Dasyuroides byrnei (Marsupialia: Dasyuridae) , while resting and running.

Abstract

The Kowari (Dasyuroides byrnei) , a small desert-dwelling carnivorous/insectivorous marsupial, has rates of oxygen consumption (VO2) at rest close to those expected for a dasyurid of that size (111 g). At each ambient temperature tested (15, 25 and 33° C) running VO2, was elevated above resting rates, with a direct relationship between VO2, and running speed. Rates of evaporative water loss (EWL) during running also were elevated above those while at rest , but not to the extent of VO2. We estimated that a foraging D. byrnei can offset evaporative water deficits by metabolic water production and that an insectivorous diet (metabolic plus preformed water) will readily provide all of the animal's water needs either at rest or while active on the surface at night.