Life in Extreme Dryness and Heat: A Telemetric Study of the Behavior of the Diamond Dove Geopelia cuneata in Its Natural Habitat

Abstract

Daily activity cycle and thermoregulatory behaviour of free-ranging Diamond Doves Geopelia cuneata were recorded in the Hamersley Range National Park in north-west Western Australia. Birds were equipped with miniature HF-transmitters (mass approx. 1.6 g, representing 4-5% of body mass) and radio-tracked from sunrise to sunset over a period of 30 days. Transmitters glued onto the tails of the doves did not cause any obvious alteration in the birds' behaviour. For comparison, the behaviour of Spinifex Pigeons, Zebra Finches and various raptors was observed simultaneously. The observations were interpreted with reference to the results of previous laboratory studies. Diamond Doves were active almost throughout the day, even when ambient temperatures were highest. In contrast, the activity of potential predators and food competitors was reduced during this time of day. Only the equally heat-tolerant Spinifex Pigeons were also active during the whole day. However, they occupy another niche due to different habitat selection. Extraordinary physiological adaptations evidently enable Diamond Doves to occupy time and space niches in their dry and hot habitat in Australian semi-desert regions that cannot be used by less heat-tolerant species. During the hottest time of the day they were able to forage while potential predators and food competitors were absent.