Temperature as an early warning signal of honeybee colony failure

This dataset consists of time-series of temperature, survival, and brood count data of Apis mellifera honey bee colonies for the development of early warning signals of colony death. Data were obtained from hives in California in 2016-2017 or Sydney in 2018 or 2020. Hives were opened multiple times to evaluation brood levels and survival.

Methods
Temperature was recorded every 15 min using sensors with a 0.0625 °C precision (iButton Thermochron model DS1922). Every two months, sensors were removed for inspection, data download, and replacement, occasionally creating gaps in the temperature records. Because accessing sensors required opening the hive and thus some level of colony disturbance, records for the first 2 h after sensor installation were removed.

During hive evaluations, the survival status of colonies was noted with colonies considered dead when 300 bees or less were left in a hive. In addition, bees were brushed off the frames, frames were then photographed using Nikon or Canon DSLR cameras. Capped brood cells were counted from photos using ImageJ or Combcount.