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Q and A-03-08042017135752

Susan Carpenter at UW Arboretum Visitors Center on Aug 4, 2017 in Madison, WI. PHOTO BY SAIYNA BASHIR

Susan Carpenter has been the University of Wisconsin Arboretum's expert on the rusty-patched bumble bee, which joined the endangered species list earlier this year.

The native plant gardener at the University of Wisconsin Arboretum has been working with many people to collect information about the bee. The Arboretum offers workshops on how to survey and attract it by growing the native plants it needs to survive. Southern Wisconsin is one of the remaining habitat regions where the rusty-patched bumble bee is found . Carpenter became fascinated with them after receiving a photo from a bee expert who visited the Arboretum in 2010.

Carpenter is leading a workshop about the bees on Saturday, August 12, 9:00 a.m. to 12:00 noon. The session will include information about the bumble bee life cycle, some bee ID, tips for doing photo surveys, and uploading data to Bumble Bee Watch. Weather permitting, participants will go outdoors, look for and photograph bees at the Arboretum. Advance registration is required by emailing

The Cap Times sat down with her to discuss the rusty-patched bumble bee and what led to it becoming endangered.

How did you first discover the rusty patched bee at the Arboretum?

About six years ago an expert visiting the Arboretum took a picture of a bumblebee. He identified it as the rare rusty patched bumble bee and was curious to know whether we had seen more of them. This bee has been lost over most of its range; now it's restricted to an area of the upper Midwest from Minneapolis,down into Wisconsin, Iowa, and Illinois Where is it sighted, there are never more than a few individual bees present. When we received the picture

we had no idea how many kinds of bumble bees lived here or if we would find more rusty-patched bumble bees. So staff and students started to document them with photography. We began a citizen science project, where volunteers take photos, upload them, and expand what we know . 

What does the citizen monitoring project entail?

Basically we photograph bumble bees throughout the season here at the Arboretum in our gardens, prairies, savannas, and woodlands.. We would like to know which bumble bees live here and which plants they use. We’ve documented at least 12 species of bumblebees at the Arboretum. For comparison in southern Wisconsin there are about 14 different species. Some of them are extremely rare; some are common Within Wisconsin altogether there are 20 different bumble bee species; some are only found in the northern part of the state. We also look for bumble bee nests, which are often underground or hidden. Little is known yet about bumble bee nesting. 

We upload photos to which is an easy-to-use web portal that maps all sightings submitted across North America. It includes identification tools, and all bee IDs are verified by experts so you can learn which bees live in your area. 

What is the bee's life cycle?

Late in the summer, the bees that will become the following year’s queens hatch, develop and fly from the nest. They mate and feed briefly, then dig into soil where they spend the winter. All of the other bumble bees from the current year do not survive to the next year.  Early in the spring, the bee queens emerge to forage and start her nest. She has to find flowers in bloom to collect nectar and pollen and she has find a suitable nesting spot.  This could be a ground squirrel hole,hollow log, a hollow root,or a compost pile. The rusty patched bumble bee, is thought to nest underground in a space as big as a softball. She lays eggs in the nest, and begins to raise the first batch of worker bees. When the workers are mature, they take over the pollen gathering duties, and the queen remains in the nest.  As more workers are produced, the colony grows.  In late summer, the queen produces male bees and the future queens for the following year.  

How can you identify a rusty patched bumblebee?  

Both female workers and males have this color pattern on the abdomen—the first segment is yellow and the second segment is yellow with a rusty patch toward the front of the bee. The queen is larger than workers or males , and she has two plain yellow abdominal segments, with no rusty patch. We also look at other small features that can help distinguish this species from other similar ones.

What's the best way to take a picture of the rusty patched bee?

To photograph the important features, it’s best to take several pictures to get a side view, top view, and the shape of the face, which can be determining characteristics. We take pictures of all the bumble bees to learn as much as we can. We encourage anyone taking photos of bumble bees to upload photos to

Why is the rusty patched bee endangered?

There isn’t a single simple answer. The stressors for bees are loss and fragmentation of habitat. Ideal bee habitat has rich floral resources from early in the spring all the way into the fall. For our region, you need to have continuous bloom from April to September. They store a little bit of nectar in the nest but they can’t survive for long without flowers to visit.

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They also need nesting habitat, as mentioned before. And they need loose soil for over-wintering habitat, although not much is known about what's required for that.

Other stressors are disease and pathogens, pesticides such as insecticides, as well as climate change and extreme weather events. One stressor may increase the effect of another.

Where stressors are removed or minimized, there is more likely to be a healthy landscape for bees (and other pollinators).

Will the Arboretum look at the population count of the bees in the future?

Yes. Our citizen science project continues. There will be much more research here and in other places. When an (endangered species) listing comes out, interest grows because people realize how important and urgent it is to learn as much as we can to protect the species. We can create and improve habitat, and cut down on stressors as much as possible. The Arboretum has habitats the bees use year after year, with many different kinds of native Wisconsin plants and some ornamental garden plants- floral resources that support bumble bees and other pollinators.

One of the things we're looking at is which plants the bees are using throughout the year, from early to late season. We can use much more information about where the bees live and what kinds of flowers they're using. The power of citizen science comes from people participating, taking photos and uploading them, then seeing the patterns emerging...that's really the strength of it.

What can people do if they want to attract the rusty patched bee and other bees? 

Grow a wide diversity of native plants and garden plants that bees use. Prairie and savanna pl Leave nesting places in your yard, Avoid using insecticides, especially systemic insecticides. Also document the bees you see, and photograph them. There is a plant called bee balm. This is one plant to grow if you want to attract and look at bumblebees. There are also many more plants to choose, which you can see at the Arboretum and many inspiring prairies, savanna, woodlands, and wetlands in the region.


Katelyn Ferral is The Cap Times' public affairs and investigative reporter. She joined the paper in 2015 and previously covered the energy industry for the Pittsburgh Tribune Review. She's also covered state politics and government in North Carolina.