The past few years have been rough on the bee. Colony collapse disorder, for example, threatens commercial honey bee populations; possible culprits for the massive bee disappearance include parasites and overuse of pesticides, as well as stress from overcrowded bee yards.
Rusty patched bumblebees, though not used commercially, are key pollinators for wild plants and crops such as apples and onions. They've disappeared from about 87 percent of their historic range, making this discovery all the more rewarding.
"We thought this bumble bee was extinct," says Bill McShea, a scientist at the Smithsonian Conservation Biology Institute who surveyed the bees. "Finding one bee, well this is the stuff conservationists live for."
Where there's a worker bee, there's a colony, Roulston says. The rusty patched bees will spend winter underground, and in the spring the researchers hope to uncover exactly where the rare bees are living.