Thermal relations and water balance in the day frog, Taudactylus diurnus, from an Australian rain forest

Abstract

Body temperatures, critical thermal maxima, tolerance to water loss, and rehydration rates were measured for T. diurnus in the rain forest on Mt. Glorious, south-eastern Queensland. Body temperatures ranged from 13.6 to 22.8'C (mean 1 8 . 4 i l .g°C) for adults and from 14.0 to 23.8"C (mean 19.852.4"C) for juveniles. Body temperatures were significantly higher in juveniles. The critical thermal maximum for T. diurnus was 31 . l i l . 2 " C and ranged from 28.4 to 33.7"C. Minimal activity temperatures appear to be reached in winter months. The mean lethal water loss for T. diurnus was 26.2 & 4.3 % of the original weight; this species shows less tolerance to desiccation than other Australian anurans that have been studied.