In the last three years, on behalf of the Pennsylvania Bee Monitoring Program, 20 master gardeners from around Pennsylvania have netted and trapped more than 25,000 specimens across 25 counties. They collect bees from city parks and among forest clearings, beneath power line rights-of-way and in their own backyards. And their work, done between March and November each year, has transformed what researchers know about wild-bee abundance and diversity in the Keystone State.
"They collect like fiends," said Sarah Kania, an entomologist at Pennsylvania State University who receives, identifies and catalogues every bee the beeple find. "Last year was a huge year; we got 16,000 bees. I saw bees I'd never seen before."
Peg Friese, an environmental educator in Chester County and one of the beeple, figures that about 2,000 of those were bees she collected. That topped the previous year's total of 800. "It's addictive," she said.
Stephanie Szakal, a retired IT professional who has collected more than 40 species in densely populated Allegheny County, agreed. "I had never really looked at or noticed wild bees. Now I can't go anywhere outdoors and not look for them."
Together, the beeple have provided an unprecedented dataset for Penn State entomologists who are trying to get a handle on what is happening to wild-bee populations as the climate changes.
"It's incredible how much time and energy they are willing to give for our research," Kania said. "We can only do the work that we do because of the work that they do."
Motivation for the project began almost a decade ago, Margarita López-Uribe said, who runs a Penn State lab devoted to the study of wild bees. In 2016, she and her colleagues began work on a new state checklist for bees in Pennsylvania, collecting specimens and scouring online observations, academic studies and natural history collections.
"We found that knowledge of biodiversity was strong around universities and university towns," López-Uribe said. "But for most counties, there was no information recorded." Researchers knew from the outset, for example, that more than 400 species of wild bees occurred in the state, but some counties had just two observed species on record.
"Biased sampling is a struggle everywhere," Kania said. "But it's important to fill in those gaps, especially with climate change. We need to know what's arriving, what's disappearing and what species might be on the move."
Given that one-third of the world's food requires pollination, what we don't know about bees can hurt us. But gathering new data would require boots on the ground, and there are only so many entomologists with so many hours in the day.
"I can't divide myself into 20 scientists," López-Uribe said. So she did the next best thing: She recruited master gardeners.
Every state and the District of Columbia has a master gardener program, typically offered through a university, in which volunteers receive training on a range of horticultural topics. To maintain an active certification, master gardeners must volunteer a certain number of hours each year, giving lectures, writing articles or tending a community garden.
"If you've taken the time to get the certification, you already have a very natural connection with nature," López-Uribe said. Master gardeners also tend to be retirees, she added, with more time and flexibility than the average citizen scientist.
The Pennsylvania Bee Monitoring Program officially launched in 2021. Each year, López-Uribe and her colleagues host an in-person training session to teach participants standardized protocols for how to trap or net bees; how to wash, dry and pin their specimens; and, finally, how to use a microscope to identify each species (or do their best trying). At the end of the workshop, they must recite the insect collector's oath, promising to treat insects humanely and kill them only in the name of research and education.
Armed with traps, nets, microscopes and a newfound confidence, they are then deployed across the state to catch bees in their own neck of the woods.
"Most people know bumble, honey and carpenter bees," said Szakal, who was once a beekeeper. Wild bees, she explained, are mostly solitary creatures, with completely different life cycles and behaviors.
Wool carder bees, for example, make their nests in preexisting cavities such as hollow sticks, pine cones or snail shells. Males are extremely territorial, defending their favorite plants by crashing into other bees with their spiny abdomen.
"Now I can see them from 10 feet away and know exactly what they are," Szakal said.
"There are some really unusual and very cool bees out there," said Friese, who has found 69 species in her 1.3-acre backyard alone. Among her favorites is the calliopsis cuckoo nomad, a tiny red bee that lays its eggs in the nests of other bees. For each specimen, volunteers note the time, location and weather of the collection site. Over the past three seasons, the beeple have set 662 county records - meaning a new species was reported for the county - and seven state records, bees that had never been recorded in Pennsylvania.
Nash Turley, a postdoctoral researcher in the López-Uribe Lab, said even he was surprised by the number of records the beeple set, many of them of occurring right in their yards "These were species that we would expect to be here, it's just that there have not been large-scale efforts to find them."
Turley was the lead author on a recent study that compared the performance of the master gardeners with users on iNaturalist, a citizen scientist platform that researchers now use to glean hard-to-get data. Even though 10 times as many people contributed to iNaturalist data across a wider geographic range, they documented only two-thirds as many bees and only one-third as many species as the master gardeners.
All of that gain has come with a little pain, which the beeple have endured with aplomb. "I've been stung a couple times," says Tony Shaw, a volunteer in Dauphin County. "But the bee didn't know what was going on, I just got my finger in the way of the stinger."
Only occasionally are they deterred. "I was chased by a swan while trying to monitor a patch of spring beauties," Friese says. "I decided to find a patch of spring beauties somewhere else."
According to López-Uribe, the true impact of the project reverberates far outside her lab.
"Something that the papers and the science doesn't capture is the social effect of the project," she said. "These master gardeners that we are training are disseminating information at the local level. There's a social reach that's hard to quantify."
"My favorite part has been telling other people about the project," said Szakal, who gives frequent lectures to local garden clubs. "When I show people a bee under a microscope, they are always dumbfounded about how beautiful they are. They just marvel."
Tammy Jamieson, a master gardener and pharmacy technician in Southwest Pennsylvania, has gotten used to being approached by strangers. "When they see me out collecting, they immediately ask if I'm collecting butterflies," she said. "Then I get to explain what I'm doing and why I'm doing it. I get to preach just a little bit on behalf of these amazing little critters."
The public, in turn, are often supportive. Recently, Jamieson got to evangelize to a curious family while collecting in an overgrown lot next to a grocery store. "As they pulled away, I heard the mother say, 'Good luck, sister!' That was exciting to me, that someone got it."
The beeple are also eager to share with others what they have learned about what wild bees need to survive and thrive.
"A lot of people are fastidious about cleaning up their lawn in the fall, getting it ready for next spring. I was like that too," Shaw said. "But you should leave it alone until spring. All that dead stuff provides places for wild bees to overwinter. There are lots of eggs in that debris, and lots of food for larvae."
In Chester County, Friese has also stopped raking autumn leaves, using chemicals or spreading mulch, which can make it difficult for ground-nesting bees to dig tunnels.
Szakal, who was already committed to growing native plant species, says that following bees around has changed how she decides which plants to add to her yard, including varieties she had previously written off . "Bees use another set of criteria to determine the value of a plant," she said.
As cooler fall temperatures arrive, Szakal and her fellow beeple are still out collecting specimens, aiming their nets at wild-bee magnets, including goldenrod and aster.
The end of the collection season "feels a little like the day after Christmas," Shaw said. "I always ask myself did I collect enough samples? Where else could I have sampled? Could I have sampled one more time?"