Date of Award
Master of Science in Integrative Biology (MSIB)
First Committee Member
Second Committee Member
Climate warming has been identified as one of the primary factors causing worldwide pollinator declines. One of the most at-risk groups of pollinators is bumble bees (Bombus spp.). Bumble bees are common, widespread, and key pollinators of a wide range of crops and wild plants. Although studies have examined the thermal physiological traits of individual bumble bees to understand how they may be impacted by climate warming, little to no studies have examined how climate warming may impact whole bumble bee colonies both in their ability to thermoregulate their nest for their brood or in their ability to forage for food. Here, we set out to investigate how climate warming will impact bumble bee colonies by affecting these behaviors. To do this, we first measured temperature in simulated nests both above- and belowground as well as air temperature from March to November of 2021 to understand what temperatures bumble bees experience in different environments. To understand how warming may impact nest thermoregulation and foraging, we examined the rates of these behaviors in response to ambient temperature. Our results show that climate warming will give bees more time to forage and require bees nesting both above- and belowground to heat their nests less, but bees nesting aboveground may have to cool their nests at possibly unsustainable levels. It appears that the direct impact of climate warming on bumble bees is overall beneficial, thus climate warming may be driving bumble bee declines through indirect impacts such as host plant phenological mismatches.