Study Catalogs Black Hills Bees for Biology Research

South Dakota State University researchers will inventory native species of bees in the Black Hills region starting in late 2009.

SDSU Plant Science Entomologist and Professor Paul Johnson said biologists know that at least 100 species of bees are found in the region. But there’s a possibility that perhaps 80 or more other unknown species could be found there.

“Our knowledge base right now is so poor that we know there are more species out there than have been formally reported,” Johnson said.

“Very simply we want to find out what species are there currently, what habitats they occur in, and in the case of those that are regular flower visitors and pollinate on a regular basis, we want to ascertain which flowering plants they visit or which ones they seem to prefer at different times of the year — the focus being on which species are out there.”

Knowing what species of bees are there and what plants they visit will help biologists better understand the entire Black Hills ecosystem. Johnson said at least 75 to 80 percent of the flowering plants in the Black Hills are dependent on bees or some other species of insect for pollination, or the transfer of pollen from the male flower parts to the female flower parts.

For most meadow and prairie plants, including many trees and shrubs, he added, bees are the most important pollinators. Bees are also recognized as valuable indicators of ecological health because of the niche they fill in servicing the plants in a region.

“You can use the diversity of the bees in an area as a relatively easy-to-sample proxy for the condition, the overall quality, of those habitats,” Johnson said. “If certain bees disappear, it’s an indication that something is wrong. Bumblebees, for example, are very sensitive to parasites and diseases. Native bees are particularly sensitive to pesticide use, including herbicides.”

The study looks at the Black Hills eco-region, which also includes some of the surrounding prairie and the Bear Lodge Mountains. SDSU researchers will gather voucher specimens and record detailed information about where and when they were collected. Part of the problem with existing information, Johnson said, is that it sometimes doesn’t give biologists enough information about whether a specimen came from higher elevations in the Black Hills, or from down at the edge of the prairie. That doesn’t tell much about the plant communities a species of bee is using.

“It’s the habitat associations and the flower associations that are critical for putting the whole story together and understanding the dynamics of the environmental changes in the Black Hills using the bees as proxies,” Johnson said.

A grant of nearly $50,000 from the South Dakota Department of Game, Fish and Parks is funding the three-year study.