Determining the critical thermal limits of wild and managed honey bees, Apis mellifera

Honey bees (Apis mellifera) contribute $16 billion dollars annually to the world’s economy. Despite their importance, we see annual losses of managed populations around 30% due to pests, parasites, and pathogens. Furthermore, beekeepers also worry about a changing climate and how to mitigate additional colony losses associated with this factor. One avenue that is understudied are populations of wild honey bees that are scattered throughout the U.S. They live without any human intervention as such they have been allowed to locally-adapt to their environmental conditions. There is a large population of wild honey bees located at the Welder Wildlife Refuge (WWR) near Sinton, Texas, that has been free-living for over thirty years. I propose to compare the critical temperature maximum of three different populations: the wild population at the WWR, a managed population that has been allowed to adapt local environmental conditions, and managed colonies that were purchased from California. To test these differences, we made a temperature rig to expose individual honey bees to an increase in temperature at the rate of 0.25C/min. We found there a significant difference in the Ct_max between treatment groups. Perhaps indicating wild colonies can handle acute temperature stress better than managed colonies.