2019 Summer Undergraduate Research Program (SURP) Symposium
Presentation Type
Open Access Poster Presentation
Keywords
Butterflies--Effect of habitat modification on; Prairie conservation;
Abstract
The conversion of grassland habitats and intensification of row crop agriculture over the last several decades have driven declines in native pollinator populations throughout the Midwestern USA. These declines in native bee and butterfly abundance have negative ecosystem consequences due to these insects’ important ecological roles as pollinators of vegetable crops and other plant life. The United States Department of Agriculture’s Conservation Reserve Program Pollinator Habitat Initiative (CP-42) aims to conserve native pollinators by increasing pollinator habitat throughout the United States. However, since the program’s inception in 2011, there has been little monitoring of its effectiveness and no documentation of how the establishment of pollinator habitat affects local pollinator populations. The CP-42 program primarily focuses on local factors (vegetation characteristics within fields); however, landscape factors (land cover surrounding CP-42 fields) is also known to affect pollinator abundance and community composition. This study compares the effects of local and landscape variables on butterfly abundance in CP-42 plantings in order to determine which affect butterfly populations more strongly. We sampled thirty, 3-year old CP-42 sites within a 60 mi radius of the University of Northern Iowa in 2018 and 2019. We surveyed each site for local floral abundance and diversity by conducting vegetation surveys along transects. For landscape variables, we used ArcGIS to create a 1 km buffer around each site then used a raster data set to calculate the percentage of land cover types (cropland, grassland, wetland, and forest). We then modeled total butterfly and monarch (Danaus plexippus) butterfly abundance as functions of the two local and four landscape variables and identified the best-fitting models using stepwise AIC analysis. Both local and landscape variables affected butterfly abundance in CP-42 plantings. Floral diversity, but not floral abundance, had a strong positive effect on both total and monarch butterfly abundance in CP-42 fields. Among the landscape variables, cropland and grassland cover both negatively affected total butterfly and monarch butterfly abundance. These results suggest that both local and landscape effects are significant factors to consider when selecting farms for enrollment in the CP-42 program and highlight the importance of promoting floral diversity in CP-42 seed mixes.
Start Date
2-8-2019 11:30 AM
End Date
2-8-2019 1:30 PM
Event Host
Summer Undergraduate Research Program, University of Northern Iowa
Faculty Advisor
Mark Myers
Department
Department of Biology
Copyright
©2019 Emma Simpson, Kate Sinnott, and Mark Myers
File Format
application/pdf
Recommended Citation
Simpson, Emma; Sinnott, Kate; and Myers, Mark, "Local and Landscape Effects on Butterfly Abundance in CP-42 Plantings" (2019). Summer Undergraduate Research Program (SURP) Symposium. 3.
https://scholarworks.uni.edu/surp/2019/all/3
Local and Landscape Effects on Butterfly Abundance in CP-42 Plantings
The conversion of grassland habitats and intensification of row crop agriculture over the last several decades have driven declines in native pollinator populations throughout the Midwestern USA. These declines in native bee and butterfly abundance have negative ecosystem consequences due to these insects’ important ecological roles as pollinators of vegetable crops and other plant life. The United States Department of Agriculture’s Conservation Reserve Program Pollinator Habitat Initiative (CP-42) aims to conserve native pollinators by increasing pollinator habitat throughout the United States. However, since the program’s inception in 2011, there has been little monitoring of its effectiveness and no documentation of how the establishment of pollinator habitat affects local pollinator populations. The CP-42 program primarily focuses on local factors (vegetation characteristics within fields); however, landscape factors (land cover surrounding CP-42 fields) is also known to affect pollinator abundance and community composition. This study compares the effects of local and landscape variables on butterfly abundance in CP-42 plantings in order to determine which affect butterfly populations more strongly. We sampled thirty, 3-year old CP-42 sites within a 60 mi radius of the University of Northern Iowa in 2018 and 2019. We surveyed each site for local floral abundance and diversity by conducting vegetation surveys along transects. For landscape variables, we used ArcGIS to create a 1 km buffer around each site then used a raster data set to calculate the percentage of land cover types (cropland, grassland, wetland, and forest). We then modeled total butterfly and monarch (Danaus plexippus) butterfly abundance as functions of the two local and four landscape variables and identified the best-fitting models using stepwise AIC analysis. Both local and landscape variables affected butterfly abundance in CP-42 plantings. Floral diversity, but not floral abundance, had a strong positive effect on both total and monarch butterfly abundance in CP-42 fields. Among the landscape variables, cropland and grassland cover both negatively affected total butterfly and monarch butterfly abundance. These results suggest that both local and landscape effects are significant factors to consider when selecting farms for enrollment in the CP-42 program and highlight the importance of promoting floral diversity in CP-42 seed mixes.
