Conservation groups and scientists want federal agricultural authorities to start regulating shipments of commercially domesticated bumblebees — used to pollinate crops — to protect wild bumblebees from diseases threatening their survival.
The groups says that four species of bumblebees once common in the United States have seen drastic declines — and the evidence points to diseases spreading out of greenhouses that use domesticated bumblebees.
"This is the tip of the iceberg," says Scott Hoffman Black, executive director of the Xerces Society, an insect conservation group based in Portland. "Bumblebees need to be regulated or we may see other diseases spread to bumblebees and potentially other bees."
Besides pollinating wild plants, bumblebees are responsible for pollinating about 15 percent of all the crops grown in the U.S., worth $3 billion. Demand has been growing as supplies of honeybees decline, especially for hothouse crops such as tomatoes, peppers and strawberries, and field crops such as blueberries, cranberries, raspberries, squash and watermelon.
Two European companies produce commercial bumblebee hives sold in the US: Koppert Biological Systems Inc., of the Netherlands, and Biobest Biological Systems of Belgium. Telephone calls to Koppert's office in Canada and Biobest's office in Michigan were not immediately returned.
The Animal and Plant Health Inspection Service did not immediately return telephone calls and e-mails for comment.
The Xerces Society, Natural Resources Defense Council, Defenders of Wildlife and University of California, Davis entomologist Robbin Thorp formally petitioned the US Department of Agriculture and its Animal and Plant Health Inspection service. They want to prohibit shipping commercially domesticated bumblebees and hives outside their native range, and to certify that domesticated bumblebees are disease free.
The petition cited steep declines in recent years of the Franklin's and Western bumblebee in the West, and the rusty-patched and yellow-banded bumblebee in the East.
Nine prominent entomologists signed a letter in support of the petition.
"A major threat to the survival of these wild bumblebee pollinators is the spread of disease from commercially produced bees that are transported throughout the country," says the letter, signed by University of Kansas entomologist Charles Michener and others.
Black says they wanted to work with federal authorities to control the spread of disease before taking the next step, seeking Endangered Species Act protection for the bumblebees.
While research has yet to conclusively blame a specific disease shared with domesticated species, the petition cited studies showing domesticated bumblebees regularly escape greenhouses and one bee can infect another when they come in contact gathering pollen.
Unlike honeybees, which came to North America with the European colonists of the 17th century, bumblebees are natives. They collect pollen and nectar to feed to their young but make very little honey.
A 2007 National Academy of Sciences report blamed the decline of pollinators around the world on a combination of habitat loss, pesticides, pollution and diseases spilling out of greenhouses using commercial bumblebee hives.
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