On March 21, the rusty-patched bumble bee, Bombus affinis, officially became the first bumble bee listed for protection under the Endangered Species Act. This designation recognizes this important pollinator’s precarious position in the face of multiple threats to its survival. It also provides some of the tools necessary to begin to reverse its decline.
We must take action now to prevent the extinction of the rusty-patched and other imperiled bumble bees and foster native pollinators to maintain agricultural productivity and healthy ecosystems. While federal regulations will provide some protection for this species, there are steps you can take in your own community to support the survival of these bees.
Bumble bees like the rusty-patched bumble bee are crucial for gardens, orchards, prairies, woodlands, and wetlands. They transfer pollen from flower to flower in many plant species, resulting in the production of fruits and seeds. In turn, we and other animals rely on plants, fruits and seeds for our survival and health. Bumble bees are especially efficient at pollinating vegetables like tomatoes and peppers, as well as many commercially important fruits.
Over the last two decades, the rusty-patched bumble bee has disappeared from most of its original range, and its remaining populations are small. The major threats to this and other pollinators include habitat loss, disease and pathogens, pesticides, and a changing climate. Unlike honeybees, bumble bees do not store honey, making them more susceptible to gaps in availability of flowers and extreme weather events.
The rusty-patched bumble bee only exists in small populations in a few areas of the upper Midwest. It is still found in southern Wisconsin, including at the University of Wisconsin–Madison Arboretum, where our restored prairies, savannas, and woodlands provide the diverse native plant habitat they need to survive. The Arboretum invites visitors to observe and learn about bumble bees, and we train students and volunteers to help monitor them. The landscapes maintained by the Arboretum help us learn how to restore and enhance pollinator habitat.
Homeowners, community members, school gardeners, farmers—everyone—can help protect the rusty-patched bumble bee and other native pollinators. Even if you live outside of its range, these actions will help support your local bees and other pollinators.
Most importantly, plant a wide variety of native plants that provide continuous blooms throughout the season. Consult the Xerces Society, Pollinator Partnership, or local experts to learn which native species will support pollinators. Plant masses of flowers close together in gardens and yards to help attract bees. Encourage neighbors to plant pollinator-friendly wildflowers or gardens to create a larger network of pollinator habitat. Avoid using pesticides, especially systemic insecticides that persist throughout the plant or in soils. Check that plants and seeds purchased from nurseries are not pre-treated with systemic insecticides.
Farmers and rural landowners can include pollinator habitat to encourage crop pollination and maintain healthy ecosystems. Improve pollinator habitat in hedgerows, uncultivated edges, roadsides, and on recreational or conservation land.
You can also provide places for bumble bees to nest, while making sure not to disturb nests that you find. Bumble bee colonies are often underground, or in compost, rock walls, hollow logs and under bunch grasses. Nests are occupied for only a year. Unlike ground-nesting yellow jacket wasps, bumble bees have small colonies and are rarely aggressive.
Make a habit of photographing and monitoring bumble bees and other pollinators. You can submit your photos to Bumble Bee Watch to help track both rare and common bumble bees. Get involved in local gardening and conservation groups to carry out pollinator protection plans.
These practices will support the rusty-patched and other bumble bees where they live, support other species, provide agricultural benefits, and give us a more complete picture of our essential pollinators. As spring arrives and the bumble bee flight season begins, you can help maintain these bees as crucial links in our food supply and healthy landscapes.