PARENT SESSION
Poster Session #2: Plant-Animal Interactions.
Monday, August 6, 2001. Presentation from 10:30 AM to 12:00 PM. Exhibition Hall
8
Native bee and fly visitation to two woodland herbs along a forest fragmentation gradient.
Jean, Robert1, Scott, Peter1, 1
ABSTRACT- Spring wildflowers of the Midwestern deciduous forest have historically been visited by a notably diverse set of insect pollinators, especially bees and flies. In west-central Indiana, the landscape has a substantial but fragmented forest cover. We examined local bee and fly diversity and visit rates to two wildflower species at 6 sites, each with intact native flora but differing in the percentage of forest cover at a scale of 1 square kilometer (range: 20-80% cover). We recognized 3 categories: sparsely, moderately, and heavily forested sites. Visit rates of bees and flies to Claytonia virginica and Erigenia bulbosa did not differ significantly between forest cover categories. Species richness of bee visitors ranged from 6 to 15 per site, and showed no obvious trend in relation to forest cover. Two species of andrenid bee, Andrena carlini and A. erigeniae, accounted for 61% of bee visitors and were each present at all sites. Very few honey bees were seen. Standing crops of Claytonia pollen were quickly depleted on warm days, indicating no lack of visitors to this woodland herb.
KEY WORDS: bee, fly, forest fragmentation, midwest