Modeling the Effects of Roadside and Meadow Foliage Management on the Dynamics of Bombus impatiens Populations
Vannoy WV. 2019. Modeling the Effects of Roadside and Meadow Foliage Management on the Dynamics of Bombus impatiens Populations. Appalachian State University
ABSTRACT: Populations of pollinators, including the common ground bumble bee Bombus impatiens, can be inhibited or suffer declines due to a lack of readily available flower resources. Flower resources can be influenced by a variety of natural and anthropogenic factors. There is evidence to suggest that regimented foliage management significantly alters the availability of pollinator-relevant flowers. Here I report on field studies testing the effects of foliage management (mowing) on the abundance of five bumble bee-relevant flowering plant species with diverse life histories. I then outline a mathematical model I developed based on B. impatiens life history to predict the impacts of mowing regimes on the bees’ population dynamics. I used flower phenology surveys to determine the inflorescence density of each of my five target flower species within two ecologically different habitat types under different foliage management regimes. These surveys indicated that intentionally cutting back foliage (i.e. mowing roadside grasslands and meadows) significantly reduced the overall number of inflorescences when all target flowers were considered as one group. When considered individually, only the flower species Solidago rugosa showed significant reduction due to mowing treatment. This observation suggests that foliage management has a negative effect on the density of flowering plants when implemented in this way. In many cases the degree of foliage management was so severe that no flowers ever came into bloom within the study sites. I then incorporated inflorescence density data into mathematical projections of the total nectar produced within an explicit landscape under different hypothetical foliage management regimes. The outcomes of this model suggest that implementing mowing practices influence the ability of Bombus impatiens to produce new queens and thus to their ability to persist in relatively higher abundance.
- Type
- Academic
- Authors
- Vannoy, William
- Date of Issue
- 2019-12
- Publisher
- Appalachian State University
- Units
- BLRI
- Keywords
- APHN, Appalachian Highlands Network, BLRI, Blue Ridge Parkway, Bombus impatiens, bumblebee, Hymenoptera, insect populations, Insecta, mowing regime, pollinators, roadside mowing, SER, Southeast Region, thesis