Project Number: 2080-21000-015-06
Start Date: Jun 01, 2011
End Date: Sep 01, 2014
The unique geography of Northern Arizona offers an opportunity to study the affect of elevation on the prevalence, phenology, and infection intensity of Bombus parasites because it is home to a variety of bumble bee species living along an elevation gradient. The Colorado Plateau rises abruptly from surrounding terrain in a formation of escarpments known as the Mogollon Rim. Not far from the Mogollon Rim, the San Francisco Peaks, which are the highest mountains in Arizona, attain an elevation of nearly 13,000 feet. Bumble bees will be sampled at bi-weekly intervals at three different elevational zones. Bumblebees of all available species at these sites will be collected, but the elevation zones will be selected such that least three target species can be collected at multiple zones so that comparisons can be made within the same host. To quantify infections by two parasites, Nosema bombi and Crithidia bombi, the digestive tract of these bees will be removed and examined microscopically for the presence of Crithidia bombi and Nosema bombi. Pathogens from positive samples will be quantified microscopically to determine the intensity of infection. Bees will be collected until workers are no longer present in the field during the fall. The following spring, queens will be collected, killed, and examined for the Crithidia and Nosema infections. The prevalence and distribution of both the bees and their parasites will then be quantified over both time and elevation to reveal what patterns are occurring in natural settings.