A routine survey turned up a small ray of hope recently when a single rusty-patched bumblebee (Bombus affinis)—thought extinct in the eastern U.S.—popped up in Virginia‘s Sky Meadows State Park (map).
Scientists first realized that this rare species, which was found in open habitats in New England, the upper Midwest, and parts of Canada, was in trouble about ten years ago throughout much of its range, says T’ai Roulston, an entomologist with the University of Virginia. The insect was last spotted in the eastern U.S. around 2009, and since then researchers have been actively looking for them.
Roulston hopes this new find will allow him and his colleagues from the Smithsonian Conservation Biology Institute to figure out why this bee is disappearing. (See more amazing pictures of bees.)
Researchers suspect that an invasive fungus called Nosema bombi, which arrived in the U.S. via commercialized bumblebees meant to pollinate greenhouse tomatoes, could be to blame. Originating in Europe, N. bombi either causes sterility in queens or shortens the life spans of workers and their queen, Roulston says.
He and his team plan to go back to Sky Meadows and the surrounding area to look for the colony the single worker bumblebee had to have come from. “There wasn’t just a single bee flying around the Blue Ridge Mountains,” Roulston says.
The question, the entomologist says, is whether this colony is a remnant and researchers just happened to catch a “last glimpse” of this species that’s more or less extinct on the East Coast. (Watch a video of the unconventional lead scientist of the Native Bee Inventory and Monitoring Program at the U.S. Geological Survey.)
It’s also possible this particular area of Virginia contains rusty-patched bumblebees that are immune to whatever has taken them out in 90 percent of their range.
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