A recent study from Northwestern University and the Chicago Botanic Garden highlights the negative effects of warmer temperatures on the Osmia Ribifloris, or blueberry mason bee. This species of mason bee is a solitary species native to North America that is known for being particularly effective pollinators as they collect more pollen than they do nectar.  They differ from other mason bees in that they only pollinate a few species of flowers.  This study focused on a community of blueberry mason bees in the Santa Catalina Mountains of Arizona that feed off of and pollinate the Manzanita shrubs in this area.  The study area consisted of 90 mason bee nests, each housing 2 to 15 bees, which were divided into three groups.  The first group of nests was painted black to simulate a warmer environment similar to that of future climate predictions for the years 2040-2099.  The second group of nests was painted white to simulate a cooler environment similar to that of the year 1950.  The black paint results in a warmer environment since black absorbs heat while the white paint would result in a cooler environment since white reflects heat.  The third group was painted with transparent paint so as to act as the control group and represent current climate conditions.   The experiment was conducted twice in back-to-back seasons and the bees were subjected to these altered environments from their early larval stage all the way through adult diapause, or hibernation. 
 
Bees in the past and current climate environment groups woke up and emerged from their hibernation in early February, which is considered normal for this species.  The bees from the simulated predicted climate environment exhibited drastically different behaviors.  These bees experienced a higher mortality rate and the bees that did emerge were smaller with lower body fat, which correlates to lower energy stores.  Typically when bees emerge from diapause it is over the course of 10-15 days.  The bees from the warmer environment, however, emerged over the course of 50 days.  This has negative implications on the availability of floral resources as well as on the likelihood of the bees finding a mate. These negative effects of the warmer environment are a result of their bodies reacting to the stress of the harsher conditions and can impact the health and stability of the blueberry mason bee population.  The bees in this particular study area could move farther up the mountain to a cooler environment, but this would put them farther away from their primary food source, the Manzanita plant.  The absence of these bees would also have a negative effect on this plant’s population stability in this region since they depend on these bees for pollination.

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​©2018 Meteorologist Stephanie Edwards