This is an article by a club member relating to internal Langstroth hive temperatures made over various summer and winter periods in 2016.  It also includes notes and comments related to hive ventilation and humidity.  Included are a number of graphs of the measured temperature variations.  The PDF article can be found in the “links and documents” page on this site under the heading “Langstroth Bee Hive Temperature Variations.”

Extracts below:

For those who may be interested in the temperature / humidity / condensation relationships, here is a Dew Point graph.

Humidity control.

Ref Homeostasis: Humidity and water relations in honeybee colonies (Apis mellifera) Michael B. Ellis 2008.

screenshot_01“An example of a 3 h experimental run at a room temperature of 35 C and with a flow of 90 % RH air into the top of the hive at 15 litres/minute.  This 90 % RH air started flowing into the hive at 10.30 and stopped at 1500 and the fanning workers at the entrance noted between these times.

This particular run shows an abnormal response during which the workers stopped fanning for over an hour (12:30 pm to 13:30 pm). The reason for the cessation of fanning is unclear but it caused hive RH to immediately increase to 80% RH. Humidity recordings were obtained by eleven humidity probes (colour lines) placed in the observation hive and the number of fanning workers (black line) was determined by observation.

Note that the bees maintained the internal RH of the hive at around 50% average by fanning with the results of no fanning obvious. ”

Temperature measurements

(click on image to expand)