Pollinators have been all the buzz in recent years as research has shown steady declines in populations. We’ve heard a lot about how pollinators are losing habitat and we need to plant more native species; or how pesticides like neonicotinoids are decimating bee populations across the country; or how our tendency for monocropping destroys the diversity of the ecosystem and the pollinators that depend on it. Overall, research regarding bees and other pollinators has come a LONG way over the past decade.
One of my favorite types of research in the natural world is – yup, you guessed it, the topic of many of our other blog posts – citizen science! If you’re just tuning in, citizen science is when folks in the general public (like you and me!!) get to help out professional scientists with super cool projects by collecting data or making observations about the world around us, and then submitting them to a project for analysis. For example, if you’re trying to get a sense of what the current bee population is in Minnesota, as in what species do we have here and how common are they, it would be an insane amount of work to survey the whole state. But, if you can recruit lots of volunteers all over the state to survey a small section and report their findings, the task becomes a bit more manageable. This is exactly what the University of Minnesota did with their Bee Atlas Program. The last survey, completed in 1919, identified 67 species of native MN bees. However, scientists think there are probably closer to 400 different types of bees in our state, so they set out to find more about them.
Researchers at the UMN wanted specifically to know more about our solitary bees (ones that do not live in hives or colonies) which are often overlooked. Many of our solitary bees are cavity-nesting bees, making nests/laying their eggs in things like old hollow plant stalks, woody stems, or tunnels in the ground. The UMN partnered with various organizations around the state, like Happy Dancing Turtle, to monitor cavity-nesting bees. They sent us a bee block, we hung it up and observed it all summer as solitary bees laid eggs inside, submitted our observations and photos online, and then sent it back to them in the Fall. They prepared them for winter storage, and patiently waited until spring when they observed what types of bees emerged from the blocks.
We observed a UMN Bee Block for three summers from 2016-2018. We currently have access to the 2016 and 2017 results. Not surprisingly, the blocks were used by a lot of different cavity-nesting species, including ants, wasps, spiders, and bees. The most common critter to use our nesting blocks over the two years were solitary nesting wasps from the Sphecidae family. These small wasps are parasitic, stocking their nesting cavities with paralyzed prey, like aphids, for the young to feed on when they emerge as larvae! They trap the aphids in with the egg by sealing the cavity up tight with tree resin, which the adults will chew through when they’re ready to emerge. We also had members of the Chrysididae family (Cuckoo Wasps) which are metallic-colored parasitic wasps that prey on the Sphecidae.
All of the bees (which are different than wasps, see chart) that have emerged from our block belong to the Megachilidae family, or the group of leaf-cutter, mason, and resin bees. We had multiple species of leaf-cutter bees reside in our bee block, evident by the chewed-up pieces of leaves they used to plug the nesting holes. Our bee block was one of only four across the state to house the Megachile inermis species! In addition, we also had multiple resin bees, which, as their name would imply plug the holes with tree resin instead of leaf pieces. There are only three known species of resin bees in the state of Minnesota!
Happy Dancing Turtle is located on the Hunt Utilities Campus, 60 acres of woods, wetland, grounds and gardens. We’ve worked to limit our mowed areas, allowed some areas to come back to trees and have a forest stewardship plan to help us manage our timber resources sustainably. In our gardens we utilize practices like multispecies cover crops and companion planting to support the soil health principles. And they are designed utilizing permaculture and agroforestry practices that further promotes diversity and habitat on a working, productive landscape. We are judicious in our use of pesticides and fertilizers, always choosing the least toxic and harmful methods based on integrated pest management theory. We are proud to have been part of the Bee Atlas program. We feel the success of our garden and of our bee blocks is due to the way we manage our landscape. Hugh Hammond Bennett, original director of the Soil Conservation Service, said it best more than 75 years ago, “Take care of the land, and the land will take care of you.”
Although the Bee Block study is over, there are other ways you can participate in citizen science programs, especially ones that are related to bees and pollinators! The UMN is still working on collecting data for the Minnesota Bee Atlas! One way to help is to take photos of the bees you find and load them into a free account on iNaturalist. Once you have an account, you can select “MN Bee Atlas” as one of the projects and start loading all your bee photos there to log your sightings! Another option would be to take photos specifically of bumblebees for the Xerces Society’s Bumble Bee Watch. This citizen science project is also looking for volunteers to observe the same route 3x per summer and record your sightings. Lastly, if you’re interested in monitoring a pollinator other than bees, the UMN’s Monarch Lab runs a Monarch Larva Monitoring Project (MLMP) where you record observations of monarch caterpillars. Every bit of data you help collect helps us learn more about our pollinator populations and the challenges that face them in the future!