Western Bumblebees Returning to West Coast?

A species of North American bumblebee that scientists deemed all but gone has re-emerged in Washington state, hinting at a possible recovery, scientists say.

Entomologists and bee enthusiasts have recently captured images of several specimens of the Bombus occidentalis flitting between flowers in one suburban park north of Seattle.

The multiple sightings, including observations of several queen bees, still don't necessarily mean the western bumblebees in the area are on the rebound, said Rich Hatfield, a biologist for the Oregon-based Xerces Society for Invertebrate Conservation, which documents such findings.

Nevertheless, "it's a pretty big deal," Hatfield was quoted by Reuters, though multiple sightings in themselves don't prove a species comeback. "It gives us hope that we can do some conservation work and perhaps the species has a chance at repopulating its range."

In 2012, a single western bumblebee, distinguished by its white-banded bottom, was discovered by an insect enthusiast in her mother's garden in the suburban community of Brier, approximately 20 minutes northeast of downtown Seattle. That was was the first sighting of the bee west of the Cascade Mountain Range in well over a decade.

Then, earlier this month, Will Peterman, 42, a freelance writer-photographer and self-described "bee nerd" from Seattle, was also in Brier when he and a group of colleagues from the University of Washington identified and photographed at least three bumblebee queens.

Peterman, however, failed to locate a bumblebee nest in the area; hives are where domesticated honeybees set up shop.

Hatfield explained the queen bees he saw would typically be expected to go into hibernation soon and then re-emerge next spring and produce more offspring.

Bombus occidentalis is one of four wild North American bumblebee lines that started to wane in population numbers about two decades ago, Hatfield said.

Scientists cite several likely factors for the bumblebee declines, including parasites, pesticides, the loss of habitats or range fragmentation.

The western bumblebee population was one of the most common bees in the Western United States and Canada, valued as a key pollinator for tomatoes and cranberries.

But it had virtually vanished from about half its historic range, which stretches along the West Coast from central California to southern British Columbia.

The species' numbers remains relatively strong in the Mountain West.

The mood among the scientists today is "almost giddy," Peterman said. "This is grounds for optimism in a story that has been really bleak."