The first-ever comprehensive study of Vermont’s bee populations has documented 70 new species — 20% of the species known to exist in Vermont — thanks to 55,000 observations from biologists and citizen scientists.
Biologists hope the data will help conserve some of Vermont’s 352 bee species in the future.
“A few species collapsed and disappeared in the late ’90s,” Spencer Hardy, the report’s lead author, said at a webinar on Thursday. “We didn’t realize it until after the fact, and it was too late to do anything. Had we had a long-term monitoring program going on, we might have been able to pick that up earlier and to address the problem.”
Fifty-five bee species urgently need more protection, according to the new report, called State of Vermont’s Wild Bees, which was issued this week by biologists at the Vermont Center for Ecostudies in collaboration with Vermont Fish & Wildlife Department. It’s a section of the Vermont Atlas of Life, a log of different species that exist around the state.
Bees are facing a number of threats, including disease, introduced species, pesticides, climate change and land use changes.
Some wild bees have contracted pathogens that come from farmed bees, Hardy said. When farmers use commercially produced bumblebee colonies for pollination in greenhouses, for example, those bees can spread pathogens to wild bumblebees when the commercial bees forage outside and come into contact with local populations, according to the report.
“This is a huge one that has been implicated in the decline of some bumblebees — pathogens coming from cultivated bumblebees,” he said.
This point sometimes causes confusion, Hardy said. Some Vermonters have told him they want to keep bees to combat species decline. But honeybees, which aren’t native to the state, can also spread pathogens — and around 95% of Vermont is within foraging range of a honeybee hive, the report says.
“They are to wild bees as chickens are to wild birds,” he said.
Still, bees kept by people for honey and other purposes face some of the same threats as wild bees, such as climate change.
Bees’ responses to climate change “will vary quite drastically,” said Michael Hallworth, a co-author of the report. “It really depends on the species.”
Even some closely related species might experience climate change differently.
“There’s going to be some climate winners, like the Eastern carpenter bee, which is predicted to increase across the state because of climate change,” Hallworth said. “And then there’s some climate losers — particularly the species that are found in the northern tier of the state that are cold weather-ish specialists.”
Some specialist bees, which sometimes rely only on a single plant, could be impacted if the plant blooms early or late because of changes in temperature.
Land use changes are also projected to affect bee populations positively and negatively.
Some changes create more open space and encourage a higher diversity of flowering plants, which is important for some generalist bees, Hardy said. Then again, those changes are likely to encourage deer populations to grow.
“These deer are browsing, preferentially, on native flowering plants and shrubs, which is potentially a stressor on plant populations, which has negative implications for specialist bees especially, and other pollinating insects in general,” he said.
More than half of Vermont bees — primarily wild — have been spending time on farmed crops, scientists found. They’ve been found on raspberries, blueberries, strawberries, apples, tomatillos, chestnuts, ground cherries, chives, oregano and potatoes.
That’s good news for farmers, who benefit from the pollination that bees provide. It could also put bees at risk if pesticides are used on the crops.
While many of the state’s wild bee populations are under threat, scientists emphasized Thursday that Vermonters can participate in their restoration.
“Even if you don’t live in one of those important bee areas or a priority survey region, it’s important to note that everything — from large meadows to backyard pollinator gardens or diverse community gardens — every one of those landscapes can help support wild bees in the state,” Hallworth said. “Even small actions can really make a big impact.”
Biologists guessed that there are still more species left to find.
The thousands of bee observations came, in part, from hundreds of citizen scientists around the state who recorded their observations on the platform iNaturalist.
“I just find that to be really exciting,” said Kent McFarland, a co-author of the report and director of the Vermont Atlas of Life, “that we’re starting to pay attention and learn about all the things that were buzzing around, and we didn’t even notice them before.”
Correction: An earlier version of this story misspelled Kent McFarland’s name.