Document Type


Date of Degree Completion

Spring 2019

Degree Name

Master of Science (MS)



Committee Chair

Jason Irwin

Second Committee Member

William Kemp

Third Committee Member

Lucy Bottcher


The relationship between low temperatures, emergence and supercooling point of Osmia lignaria were the subject of this study. One hundred sixty-eight bees were subjected to 5 pre-wintering temperature treatments (two constant temperature controls - 22oC, 14oC, one of which with and one without a 12h photoperiod, and three 12h:12h thermoperiod treatments – 14:10oC, 14:5oC, and 14:0oC) and were then evaluated in terms of emergence time and post-emergence vigor. An additional 70 bees were tested for metabolic rate and discontinuous gas exchange in response to test temperature conditions. An additional sample of 60 bees was evaluated for temperature of crystallization. Of the 168 bees which were emerged, it was found that bees held to an intermediate thermoperiod of 14oC during the “day” and 10oC at “night” emerged an average of 2 days earlier than the other treatments. During the experiment, discontinuous gas exchange was observed for the first time in this species and metabolic rates were examined in 5oC increments which ranged from 6.54 µl·g-1·h-1 at 0oC to 177.72 µl·g-1·h-1 at 20oC. Temperature of crystallization was also established as -26.4oC (±0.6oC) for Washington O. lignaria.