Entomological Society of America
St. Louis, Missouri
The influence of nest cavity temperature on fitness and diapause incidence in the solitary bee Megachile rotundata
Tuesday, November 19, 2019
America’s Center – Room 274
Temperature has non-linear effects on insect performance and can influence survival, body size, diapause incidence. Larvae of the solitary bee, Megachile rotundata, develop in nest cavities chosen for them by their mothers. Nest cavities are microclimates that differ from ambient temperatures, allowing the potential for nesting females to choose favorable cavities for their offspring. To determine the importance of cavity temperature for offspring fitness, body size and diapause incidence we tracked nest cavities temperature in the field and looked at female nesting behavior and offspring traits. We determined that females preferred to nest in cooler cavities that faced northeast or northwest. Cavity temperature did not affect offspring body size, but cavities that reached higher temperatures (hours above 40C) had higher offspring mortality. Temperature and date of nest construction influenced diapause incidence with cooler nest cavities having higher incidence of non-diapausing bees. Offspring laid earlier in the season tended to not diapause, suggesting the importance of photoperiod in regulating diapause in M. rotundata. Our results indicate that cavity temperature has a strong influence on solitary bee life history and fitness.
Join Julia and her colleagues on November 19th at the Entomological Society of America (ESA) conference in St. Louis, Missouri. Click here for conference details.

Dr. Julia Bowsher is an Associate Professor at North Dakota State University. She is interested in how environmental stressors impact insect fitness. Julia is particularly interested in determining how temperature and nutritional stress during development affect the adult phenotype, and what molecular and physiological mechanisms mediate the responses to these stressors. Bees experience many potential stressors during agricultural management and in response to climate change. Understanding how we can protect against these stresses will help build resilient populations. Read more about Julia HERE.