"Bee Counted" - Census Time for Pollinators on the Chequamegon-Nicolet NF

By Alan Barbian on Apr 4, 2010

The first comprehensive review of bee diversity since 1935 and also the first inventory of this type on any National Forest.

It's census time for all Americans including bumble bees. We rely on bees to help pollinate flowers and trees, but they need to be counted as well.

Despite their well-documented ecological importance, we know little about the bee fauna in most regions of the world. Native bees are key pollinators of economically and ecologically important trees such as maples, basswood, and cherries as well as uncommon rare species of the forest understory.

The North-Central Forest is one of the most under-sampled regions of Wisconsin. So last year the Chequamegon-Nicolet National Forest (CNNF) helped fund the first comprehensive review of bee diversity since 1935. This is also the first inventory of this type on any National Forest.

Entomology experts Dr. Amy Wolf of the University of Wisconsin-Green Bay and John Ascher of the American Museum of Natural History compiled a list of 388 bee species in Wisconsin from field surveys, previous records, and collections throughout the state. That is more than double the number of specimens known from Nicolet side of the National Forest (165 species).

"Some bumble bee species have shown an alarming decline in the past decade and last year's find of Bombus frigidus is the only record in the eastern U.S. in over 45 years" Wolf said. She also found several colonies of Macropis nuda (oligolectic bees) which specialize in collecting pollen and floral oils from the plant genus Lysimachia to use for food and nest linings. This species is doubly interesting because of the potential of finding an associated rare parasitic bee (Epeoloides pilosula) which was once thought to be extinct but recently rediscovered in the east. "We hope that relict populations may be found where the Macropis host and Lysimachia occur together" said Wolf.

Wolf and Ascher, along with others, submitted recommendations to the Bureau of Endangered Resources to list several species of bees as endangered, threatened, or special concern in Wisconsin.

Appropriate pollinator habitat management is essential. The CNNF seeks to develop a conservation strategy that provides them with adequate flower resources, especially in years of short spring and fall flowering seasons.

Results from the Forest investigation give a clearer picture of distributions and abundance of bees in northern Wisconsin, yet much remains to be discovered. Wolf added, "We plan to continue the work, searching for rare as well as common bees, keying in on pollinators of forest trees, early spring flowers, and blueberries," she said.

For more information on bees and other pollinators, contact Chequamegon-Nicolet National Forest Botanist Marjory Brzeskiewicz or visit http://www.fs.fed.us/wildflowers/pollinators/index.shtml.