Last summer, a research team led by UVA professor T’ai Roulston and members of the Smithsonian Conservation Biology Institute examined about 35,000 bees belonging to 126 species. But one bee stood out above the others.

In Sky Meadows State Park in Delaplane, Va., the team spotted a lone rusty patched worker bumblebee. Once a common sight, the species hadn’t been seen in the Eastern United States for five years and researchers believed the bee was headed for extinction.

The rusty patched worker bumblebee hadn't been seen in the Eastern United States for five years.

Bee populations have been declining in recent years and researchers are working to reverse the troubling trend. Pollination from honeybees plays a part in the production of about a third of humans’ food supply.

“In 20 years of studying bees, I have never seen a rusty patched,” says Roulston, research associate professor in the College of Arts & Sciences’ Department of Environmental Sciences and curator of the State Arboretum of Virginia. “Where there is a worker bee, there is a colony, and maybe more than one. As they’ve gone underground for the winter, we can actively look for the colony next spring, study them and what might be affecting the species.

“We’ve either found rusty patched bumblebees that have developed a resistance, or we’ve discovered one of the last colonies and will get one more glimpse before they disappear forever.”