I joined three biologists from the USFWS La Grande Field Office, two biologists from Wallowa-Whitman National Forest, a former University of Idaho biologist, a horse, and two lovely mules for a 20+ mile foray into the Eagle Cap Wilderness in the Wallowa Mountains of Oregon. We packed in along the beautiful Imnaha River, hiked through meadows full of wildflowers, and took in breath-taking views of the rugged mountains. I had to pinch myself that this could be part of my job one day!
Bumblebees are social with a structure like that of honeybees but with far smaller colonies, usually 250 individuals rather than several thousand. Queen bumblebees emerge in the spring, select nesting sites (burrows, logs, old mouse nests, etc) and lay eggs that will hatch into female workers and males. Workers collect pollen to bring back to the nest to feed larvae that will eventually develop into future queens. As summer progresses, males and new queens will emerge and mate. The males die shortly after, as do the workers, while the new queens will find a place to overwinter until spring. But wait, there’s something particularly interesting – there are cuckoo bumblebees! These are native parasitic bumblebees. Cuckoo queens will seek out established colonies, kill the resident queen and royal larvae, lay their own queens and males then make the workers serve her! Cuckoo bees usually parasitize a single species of bumblebee so finding a cuckoo bee means the species they parasitize is also present in the area.
During this trip we completed five inventory surveys and collected DNA at three sites. We processed 116 individuals, identifying 12 species including all three cuckoo bees known to inhabit the mountain range. Additionally, we found the Western Bumblebee (Bombus occidentalis), a species which will likely be proposed for listing under the Endangered Species Act, at all five sites!
Bumblebees are massively important pollinators of native plants and are under threat! Loss of habitat from urbanization as well as homogenization of the landscape in rural areas to support agriculture has created a lack of nesting sites for native bees. In addition, introduced diseases from domesticated bees from Europe have caused major population declines. Plant native plants in your gardens, stay on trails while recreating, and be sure to look for these adorable fuzzy creatures whenever you hear a “buzz buzz”.
Agency: U.S. Fish and Wildlife Service
Program: US Fish & Wildlife Service - DFP
Location: La Grande USFWS Field Office