When Americans think about bees they likely envision wax-filled hives humming with honeybees, which were brought to North America from Europe several hundred years ago. Honeybees thrived here until the mid 2000s when alarming declines sparked interest in bee conservation, native plants, and backyard beekeeping.
What people may not know is that many of America’s 4,000 native bee species, including about 50 bumble bees, have been similarly impacted by disease, pesticides, and loss of habitat. One native bee has disappeared from so much of its natural range that in 2017 it landed on the endangered species list: the rusty patched bumble bee.
Once common in the Midwest and New England, the rusty patched bumble bee, also known as Bombus affinis (BOM-bus AFF-inis) is so scarce that sightings are likely to make local headlines, as when it was spotted in 2018 at the Rogers Park Metra station by Andrea Gruver, then a master’s student doing field work on urban bee communities. The rusty patched feeds on nectar and pollen from native flowers, and the current movement toward planting native gardens to attract pollinators such as bees and butterflies might encourage their return.
Take Note of Flowers and Bees
To help entice the rusty patched – so called because of the rust-colored patch on its fuzzy back – a DePaul University graduate student created the Evanston Host Plants Initiative, a community science project documenting native wildflowers in Evanston and the bees that visit them.
“The rusty patched’s story was really compelling to me in that it’s declined over eighty five percent in the last twenty years, primarily due to pathogen spillover, habitat loss, pesticide use, and climate change,” explained Libby Shafer, who developed the initiative as her master’s thesis research for DePaul’s Environmental Sciences program.
People often feel helpless about climate change and environmental problems, Ms. Shafer said, so participating in this project could be a relatively easy way to become involved in a solution.
“Growing host plants for the rusty patched bumble bee or for other pollinators and creating habitat in yards are really simple ways that people can greatly contribute to helping the species,” she added. The U.S. Fish and Wildlife Service provides a list of 38 native plants beneficial to the rusty patched and other pollinators.
A garden is not necessary to participate – anyone can take part in the Evanston Host Plants Initiative and there are just a few steps to join. First, sign up at Natural Habitat Evanston to receive instructions and updates. Next, register with iNaturalist and join the “Host Plants for the Rusty Patched Bumble Bee” project. Then, start observing!
Members can upload photos of plants and bees to iNaturalist from their computer, or download the iNaturalist app and use their phone.
Ms. Shafer said the data will be used to examine what habitat exists for the rusty patched bumble bee throughout Evanston, make maps for each blooming period, and guide planting efforts in the future.
Why Pollinators Are a Big Deal
Flowering plants require pollination in order to reproduce. When pollen is transferred from one flower to another – by a bat, hummingbird, bee, butterfly, moth or other insect, or by wind or water – the pollinated flowers can then produce seeds to create offspring plants. About 80% percent of flowering plants around the world rely on pollinators.
Native bees – Illinois has 500 different species – and native plants depend on one another for survival and reproduction, and when pollinators suffer losses so do the plants, according to Sydney Cameron, Ph.D., Professor of Entomology at the University of Illinois at Urbana-Champaign. Her lab studies bumble bee behavior, evolution and conservation, focusing on the causes of recent bumble bee declines in North America. She also helps direct the Entomology Department’s online bee tracking project called BeeSpotter.
“Plants depend upon pollination and most of the pollination is by bees; that’s why over hundreds of millions of years bees and plants have co-evolved together,” Dr. Cameron explained. For example, some flowers require bees with long tongues to get into them and others, like sunflowers, can accommodate short-tongued bees.
Planting a range of native plants that flower throughout the growing season may help the rusty patched and other bees and insects that are also under threat to expand their range and increase in abundance, said Dr. Cameron. She also noted that popular non-native annuals such as impatiens, begonias and petunias supply little or no nectar and pollen for native pollinators.
Bees and other pollinating insects also need pesticide-free nest sites; they often nest in soil, patches of grass, and garden debris. Citizens’ Greener Evanston encourages residents to take the Pollinator Pledge to make their yards a safe haven for birds and insects. Actions include not raking autumn leaves, waiting until spring to trim plant stalks and seedheads, foregoing pesticides and lawn chemicals, mowing less, giving up leaf blowers, and reducing light pollution (which cause problems for migratory birds).
The rusty patched’s decline is the “canary in the coal mine,” Dr. Cameron said – a warning of the danger all pollinators face.
“Everything from loss of habitat to a huge percentage of greenhouse gas emissions from agriculture, to the use of pesticides, herbicides, fungicides, insecticides – all of those are harming bee populations,” Dr. Cameron said. “You’re going to do a good thing in many ways if you plant a bee garden and stop spraying, and you may bring the rusty patched back to some degree. Anything anyone could do to help bees in general would be worth doing.”
Going to Court for a Charismatic Bee
Some may be mesmerized by bumble bees and others more inclined to give them a wide berth. At least one of their champions believes the rusty patched possesses a compelling trait: charisma.
“While I think all bees are charismatic – amiable vegetarians that buzz around our gardens in the spring and summer-times – the rusty patched bumble bee is especially so,” explained Dan Raichel, an attorney with the not-for-profit National Resources Defense Council (NRDC). “It’s plump and fuzzy, lumbering in the air as it bounces from flower to flower.” While the same can be said of most bumble bees, Mr. Raichel said, it is their namesake auburn or “rusty” patch that gives them “an extra special bit of flair.”
As Acting Director of the NRDC’s Pollinator Initiative, Mr. Raichel said his job is to save the bees – specifically from neonicotinoids (“neonics”), a widely used class of nicotine-based agricultural pesticides that targets the nervous system of sap-feeding insects such as aphids. Neonics also harm beneficial insects, bees, butterflies, and birds – causing death or disorientation and illness that disrupt foraging, reproduction, and migration patterns.
“Neonics wipe out insect populations across the board that many birds rely on for food,” Mr. Raichel explained. When bugs die, birds die – resulting in a significant loss of pollinators for crops and other plants as well as shrinking bird populations, both of which have further ripple effects on the environment and biodiversity.
The NRDC has begun their fourth lawsuit on behalf of the rusty patched, this time demanding that the Fish and Wildlife Service designate critical habitat for the bees – specially protected areas that are essential for preserving an endangered or threatened species.
“They have yet to provide some of the really key protections that the Endangered Species Act affords to these bees, to make sure not only that they survive but that they recover,” Mr. Raichel said, adding that the Fish and Wildlife Service knows where populations of this bee still exist and what its historic range is so they have all the information necessary for this next step. “They now need to identify the habitat just like they would for any other species,” he continued. “We’re essentially just pushing them to do their job.”
Urban Gardens: Havens of Diversity
Andrea Gruver’s surprise discovery three years ago of rusty patched bumble bees in a “small weedy patch of flowers” near the Rogers Park Metra tracks is still a local triumph. At the time, she was investigating the effect of urbanization on bee communities in the Chicago area for her master’s degree in Plant Biology and Conservation, a joint program between Northwestern University and the Chicago Botanic Garden.
Mr. Gruver figured she had a slim chance of spotting the rusty patched at any of her eight city and north suburban Metra station field sites; when she spotted two she quickly photographed them and confirmed their identity. She did not trap or collect the bees.
It turns out that cities tend to harbor a wider range of native plants than the suburbs, where gardeners more frequently rely on non-native plants, potent chemicals, and aggressive landscaping that eliminates beneficial insects and nesting sites. Ms. Gruver’s research found that areas high in floral diversity – including extremely urban locations with very little surrounding green space – supported more native bee species.
“This suggests that in cities if we provide diverse native plant habitats – even if they are very small areas – we can help support more bees and may see a greater diversity of bees in urban and suburban areas,” Ms. Gruver explained. “I think that every backyard garden can potentially make a difference.”
Go Native to Get the Buzz
With gardening season under way, there is still time to plant native flowers in gardens or containers. But a green thumb is not necessary to participate in the Evanston Host Plants Initiative: Sign up online and wander around town in search of bee-friendly plants.Keep an eye out for bees, too, especially a fuzzy bumbler with a little rusty patch.
“My goal for this is to bring together the community to transform their lawns and provide resources for the rusty patched bumble bee and other important pollinators,” Ms. Shafer said. “I hope to see expanded habitat and to have a more accurate account of the host plants that are in Evanston, and hope we will see the rusty patched bumble bee this growing season. It would be amazing to actually get to witness the conservation efforts working.”