Vermont’s bumble bees are in trouble. A new investigation from the Vermont Center for Ecostudies has found that more than one quarter of the fuzzy bumbles have either vanished or are suffering a serious decline.
And that’s bad news for all of us, as the species are vital pollinators. Kent McFarland, senior conservation biologist for the Vermont Center for Ecostudies, and field researcher Sara Zahendra spoke with VPR’s Mitch Wertlieb about the plight of the bumble bee.
Over the past year, several biologists and a team of 50 citizen scientists covered the state for a survey of the bumble bee population. They did surveys of roadside flower patches, visited good bee habitat, like wildflower meadows, and counted the number of bees they saw in a specific time period.
"We found that around five species have declined or actually disappeared from the state, probably within the last decade or so." - Kent McFarland, Vermont Center for Ecostudies
“We found that around five species have declined or actually disappeared from the state, probably within the last decade or so,” McFarland said.
The state has 15 species of bumble bee, and with five in decline, McFarland pointed to a number of factors, including introduced parasites. In the early 1990s, as farmers switched to hothouses for crops like tomatoes, they imported bumble bees from Europe as pollinators.
“They have a specialized way to pollinate called buzz pollination where when they get a hold of that flower, they vibrate their wings, which dislodges the pollen on the stamens in a certain way, and they’re able to have a better fruit set in the case of tomatoes,” McFarland explained.
He said the thought is that European farmers imported our bumble bee species for pollination and farm-raised them. When American farmers re-imported those species as agricultural pollinators, they may have carried Old World parasites with them.
“It was able to survive those parasites, but as the parasites escaped to surrounding farmland and got into other bumble bees species populations in North America, they didn’t fare so well, they couldn’t handle the parasites and some may actually be extinct or near extinct probably from these introduced parasites,” McFarland explained.
Zahendra said the short term ramifications of the bumble bee decline could be lower crop yields of plants like tomatoes, blueberries and cranberries.
“We won’t be able to use these bumble bees to buzz pollinate as often or as much as we have been in the past. So it could have a pretty big impact on the food that we eat,” she said.
Long term, we could see fewer forest wildflowers, which are pollinate by bumble bees.
"These are the work horses of both our farm land, our forest land. To see those disappear could have serious ramifications, both economically and environmentally."
“These are the work horses of both our farm land, our forest land. To see those disappear could have serious ramifications, both economically and environmentally,” McFarland said.
It’s not clear at this point what can be done to reverse the decline of the species. One of the bumble bees, the rusty patch bumble bee, has been proposed as potentially endangered in the United States and has already been listed in Canada. Although that species is no longer found in Vermont, McFarland said there are several populations in the Midwest.
“Maybe like the chestnut tree, which underwent a blight and nearly disappeared, but then with a lot of work we’re trying to bring it back through genetics, maybe trying to find populations that are resistant to the disease it had. We’re thinking the same thing with bumble bees, maybe we can find resistant populations out there. And because we do know how to farm these bumble bees, as has been shown for agriculture, if you had resistant populations you could perhaps repopulate the landscape with some of these bumble bees,” he said.
Zahendra also pointed to limiting the use of pesticides and the kinds of pesticides used.
“A lot of the things that people can just go and buy at Home Depot and spray on their garden, people don’t understand what it is that they’re doing to pollinators in their garden when they do that.”
