title: Field energetics of a large carnivorous lizard, Varanus rosenbergi.
abstract: Field metabolic rates (FMRs; CO2production) and water influx rates of Varanus rosenbergi were measured seasonally by means of doubly-labelled water (3H218O). Metabolic rates and water influexes were highest in summer (0.18 ml CO2g-1h-1and 17.9 ml H2O kg-1day-1) and lowest in winter (0.04 ml CO2g-1h-1and 6.5 ml H2O kg-1day-1). FMRs and water fluxes were intermediate in spring. It is estimated that a 1-kg V. rosenbergi would need to consume 4.7 kg of prey each year to remain in energy balance and that the energy commitment to egg production requires a 40% increase in the food acquisition of a gravid female in late spring and early summer. It is calculated that water influxes in summer are totally provided from food but in other seasons, particularly winter, pulmocutaneous water exchange and/or drinking are significant avenues of water intake.
authors.affiliation: Division of Wildlife and Ecology, C.S.I.R.O., P.O.Box 84, 2602, Lyneham, A.C.T., Australia.
authors.forename: Brian
authors.initials: B
authors.lastname: Green
authors.affiliation: Dept. of Biology, Slippery Rock University, 16057, Slippery Rock, PA, USA.
authors.forename: Gil
authors.initials: G
authors.lastname: Dryden
authors.affiliation: RD3, 16057, Slippery Rock, PA, USA.
authors.forename: Kaye
authors.initials: K
authors.lastname: Dryden
keywords: Doubly labelled water; Energy budget; Field metabolic rate; Varanus rosenbergi; Water influx