Temperature variation in nest boxes in eastern Australia

Nest boxes are frequently installed in Australia to provide shelter sites for arboreal mammals. Little is known about the temperatures that may be experienced inside nest boxes or the factors that may influence those temperatures. I established paired nest boxes on the south-east and north-west sides of trees at two locations in south-east Queensland to investigate the influence of nest box aspect on nest box temperature. Squirrel gliders (Petaurus norfolcensis) occupied boxes at both locations. I recorded temperatures over a 1-month period in two summers. Temperature varied by up to 20°C within a 24-h period and some nest boxes experienced temperatures above 40°C. There was no significant difference in maximum temperature with nest box aspect but south-east boxes could be 1°C cooler during hot weather. Nest box construction material, colour (brown or green) and volume (0.008 m3 or 0.025 m3) had variable influences on temperature. Nest box installations for non-flying mammals should place nest boxes to minimise extreme temperatures. Further studies are required to determine whether temperature limits the effectiveness of nest boxes at some locations.