Calling in the ‘bee-team’
By Jennifer Smith
A gentle rain falls steadily on a chilly spring day. Small, white, bell-shaped flowers bob gently on the end of a blueberry branch. Buzzing through the rain, a large, bumbling bee approaches and lands on the cluster of flowers. Grasping the flower in her jaws, the bee steadies herself, then beats her wings intensely.
Called buzz pollination, this vibration causes a shower of pollen to release from the flower; the pollen mists the bumblebee’s body, nearby flowers, and the ground below. Dutifully, the bee releases her flower and bobs to an adjacent flower as the rain continues to fall.
The unassuming work of bumblebees doesn’t adequately reflect the crucial role they play in both the human economy and the health of entire plant communities. Pollination from insects such as bumblebees is worth billions of dollars worldwide. High-value crops such as blueberries, cranberries and apples are especially reliant on bumblebees.
“For some crops, bumblebees are more efficient than, say, honeybees, because bumblebees can buzz pollinate. Plus they keep foraging in rainy or chilly weather, which is crucial for high-value crops that demand pollination in a short and early time frame,” says entomologist Dr. Knute Gundersen.
From a conservation perspective, bumblebees are essential because they support diverse plant communities. Unlike their commercial cousin the honeybee, bumblebees can’t communicate the location of good foraging areas to their hive, which means rather than focusing on one particular area, individual bumblebees will buzz pollinate many different plants.
Over the past decade, scientists began to notice rapid and widespread declines in a number of bumblebee species, including the yellow banded bumble bee and rusty patched bumble bee.
As conservationists sounded the alarm, the bees gained national attention, which grew even further when the rusty patched became the first bumblebee to be federally listed as an endangered species.
But conservationists weren’t sure where to focus with the status of many populations unknown.
More information was needed on the size and distribution of northeast bee populations. Several states in the region began conducting ambitious bumblebee surveys, funded by State Wildlife and Endangered Species grants administered by our Wildlife and Sport Fish Restoration Program.
The Maine Department of Inland Fisheries and Wildlife began documenting native bumblebees in a statewide project called the Maine Bumble Bee Atlas. This ambitious survey is possible because of an enormously valuable legion of Maine residents who volunteer on scientific research projects, called citizen scientists.
“Our department has a long history of citizen science programs,” says Beth Swartz, MDIFW wildlife biologist and leader of the Maine Bumble Bee Atlas project. “With our limited staff and resources, it would be impossible for us to undertake such a large survey without the help of these dedicated volunteers. Citizen scientists increase our ability to gather data and play a valuable role in outreach and engagement with local communities, which helps build constituency and support for native pollinator conservation.”
Since its initiation in 2015, the Bumble Bee Atlas project has trained more than 350 volunteers across Maine. Together, these dedicated citizens and state biologists have added over 20,000 new records of bumblebees found throughout Maine.
To date, Swartz and her team have confirmed at least 14 of the 18 known bumblebee species in Maine are still present, hopefully being busy bees. Excitingly, the project has detected the yellow banded bumble bee every year. Unfortunately, the project has yet to confirm the federally endangered rusty patched bumble bee is still present in Maine.
Over 800 miles to the south, staff from Virginia’s Division of Natural Heritage have worked tirelessly to inventory the state’s bumblebee species, using Endangered Species Grant funding.
Laughing, field zoologist Ellison Orcutt explained, “We call ourselves ‘the bee team.’ Our days tend to involve walking transects of flowering areas and looking for some of the biggest bees on the landscape.”
Orcutt and team identify every bumblebee they encounter. In four years, their efforts have identified 16 previously undocumented species of bees native to Virginia. But perhaps the most exciting discovery came in 2018 when the “bee team” found at least 21 rusty patched bumble bees at 3 different sites.
Many northeast national wildlife refuges have also been working to document pollinator species on their lands. In 2018, four refuges piloted a new survey protocol that specifically focused on bumblebees, working with partner scientists Dr. Robert Jean and Dr. Leif Richardson.
These surveys netted more than 1,400 individual bumblebees and found several species of conservation concern, including yellow banded and American bumblebee. Several species of cuckoo bumblebee also turned up!
Fun fact: Cuckoo bumblebees are brood parasites. Meaning that they infiltrate the nests of other bumblebees and trick them into raising the cuckoo’s young.
All these efforts, though energized by the continued presence of these declining bumblebee species, face an unusual challenge. The rusty patched bees in Virginia were found in remote areas with a lot of protected and mountainous land. Historically, however, the species was found throughout the state, in a range of habitats and land uses.
“The question becomes: have we found remnants of what used to be a widespread distribution? Or have we found a stronghold where, for some important reason, the natural environment is supporting the continued presence, or even growth and re-establishment, of the rusty patched bumblebee?” said Orcutt.
Scientists still have questions about the decline of native bumblebees and although such problems can be challenging to address, efforts like those in Maine and Virginia offer hope that bumblebee strongholds exist and that people from all walks of life are willing to work hard to find and protect native bumblebees.
The effort to conserve at-risk wildlife like the yellow banded bumble bee and recover listed species is led by the Service and state wildlife agencies in partnership with other government agencies, private landowners, conservation groups, tribes, businesses, utilities and others. It has drawn support for its use of incentives and flexibilities within the ESA to protect rare wildlife, reduce regulations and keep working lands working.
Jennifer Smith has traveled across the country studying wildlife biology, from her undergraduate studies at Humboldt State University, to monitoring ground squirrel and wolf populations in Idaho, to pursuing her M.S. studying black bears in Michigan. Her interests center around using quantitative tools to address challenging conservation issues and distilling such complex ideas into compelling narratives to engage with communities everywhere.
