Tracking Bees on Experimental Forests
At first sight, the nine plastic cups in a grassy yard at Bent Creek Experimental Forest don’t look like part of a nationwide monitoring survey. But the cups are actually simple bee traps, and a number of U.S. Forest Service facilities are part of a network of bee monitoring stations that stretch across the country. The survey was designed by Sam Droege, a scientist with the U.S. Geological Survey (USGS) Patuxent Wildlife Research Center. “If our native bees are declining like honeybees, we want to know,” says Droege. “This survey is designed to let us know whether wild bee populations – both native bees and honeybees – are healthy or not.”
Several Forest Service Southern Research Station (SRS) units are participating in the survey. Coweeta Hydrological Laboratory, and the Crossett, Bent Creek, Hitchiti, Santee, and Stephen F. Austin Experimental Forests have all placed bee traps on their property, and monitor the traps periodically, sending the captured bees to Droege for identification. James M. Guldin, project leader of the Southern Pine Ecology Unit coordinates SRS participation.
The Hitchiti Experimental Forest was the first SRS unit to get involved with the survey, and has collected data for 3 years — enough for the first set of results to come in. Although results will be most meaningful when they can be considered for many different locations, the data show that bumblebees at Hitchiti Experimental Forest have declined across the 3 years, while honeybees have become more common.
Native bee species that are only rarely found in the East have also turned up at Hitchiti, and well as in other SRS units. In fact, North Carolina got a new state record when Patsy Clinton, a technician at Coweeta, found the first recorded Nomada texana in the state. As Droege explains, “When uncommonly seen species show up, to me, it’s an indication of a high value habitat.”
Bees prefer open sunny spaces, and also rely on specific plants for pollen and nectar. Plants feed bees, and bees return the favor by pollinating the plants. Because many plant species have male and female individuals, just like mammals, they need direct interaction in order to be able to reproduce. For these plants, insect pollinators are an indispensable part of their reproductive cycle.
“Seventy-five percent of native plants require insect pollination,” says Droege. “Biodiversity and native plants are closely linked. With more native plants, more invertebrates are typically found, usually 5 times the number of plant species in a given area. Exotic plants may produce pollen and nectar, but it’s often only the bees who are not choosy –- the so-called generalists –- who will consume pollen from nonnative plants.”
For more information about the project, contact Sam Droege at sdroege@usgs.gov
For more information about the SRS role in the bee monitoring project, contact James M. Guldin at jguldin@fs.fed.us