The thermal environment of nests of the Australian stingless bee, Austroplebeia australis

The greatest diversity of stingless bee species is found in warm tropical regions, where brood thermoregulation is unnecessary for survival. Although Austroplebeia australis (Friese) naturally occurs in northern regions of Australia, some populations experience extreme temperature ranges, including sub-zero temperatures. In this study, the temperature was monitored in A. australis colonies' brood chamber (n = 6) and the hive cavity (n = 3), over a 12-month period. The A. australis colonies demonstrated some degree of thermoconformity, i.e. brood temperature although higher correlated with cavity temperature, and were able to warm the brood chamber throughout the year. Brood production continued throughout the cold season and developing offspring survived and emerged, even after exposure to very low (-0.4 °C) and high (37.6 °C) temperatures. Austroplebeia australis, thus, demonstrated a remarkable ability to survive temperature extremes, which has not been seen in other stingless bee species.