How Do Behavioral Alterations Drive Population and Community Dynamics of Rodents Associated with Intercropping Switchgrass in Pine Stands

EPA Grant Number: F13B30496

Title: How Do Behavioral Alterations Drive Population and Community Dynamics of Rodents Associated with Intercropping Switchgrass in Pine Stands
Investigators: Larsen, Angela
Institution: University of North Carolina, Greensboro
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2014 through September 1, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Fellowship - Environmental Science , Academic Fellowships

Objective:

Anthropogenic changes to the environment have the potential to alter individual behaviors, life histories and population- and community-level dynamics, but mechanisms that link individual responses to population and community changes are not well understood. This research posits that population and community dynamics will differ between control and intercropped stands, driven by alterations in individual rodent habitat selection (home range size and suitability), communication (amount of ultrasonic vocalizations, or USVs) and reproduction. This research will investigate changes in an area where switchgrass is intercropped in lob- lolly pine plantations, changes occurring at individual, population and community levels and will assess links between changes in individual behaviors and changes at population and community levels.

Approach:

Rodents in Kemper County, Mississippi, will be trapped on land owned and managed by Weyerhaeuser Company within stands established and maintained by Weyerhaeuser and Catchlight Energy LLC. Radio telemetry on individual cotton rats (Sigmodon hispidus) will estimate home ranges and identify nest sites where thermal video and acoustic recording devices will be deployed. Vegetation surveys will be conducted at all trapping stations and identified nest sites. Data analyses will use non-metric dimensional scaling and analysis of variance models to compare dependent variables within and among treatment plots and multiple regres- sions to predict population and community differences from individual changes in behavior.

Rationale:

Expected Results:

Individual cotton rat home range areas are expected to decrease where grasses are abundant; subsequently, these individuals are likely to interact with USVs more frequently using. Populations whose individuals have smaller home ranges and interact more are expected to have higher survival, recruitment and reproduction rates and therefore higher abundances. Plots with abundant grass cover are expected to be dominated by populations of herbivorous species and to have the lowest rodent diversity. Also, individual behaviors (home range size, microhabitat variables within home ranges and amount of USVs) are likely to be important predictors of population- and community-level changes.

Potential to Further Environmental/Human Health Protection

Conclusions of this study will allow a more complete understanding of the extent that habitat changes initially affect individual rodents in forest production landscapes and how those changes lead to population- and community-dynamic alterations. This study will provide necessary data to make management recommendations regarding biofuel feedstock production while maintaining a diverse and stable ecosystem. This may be the first study to use behavioral conservation methods to investigate rodent individuals, populations and communities.

Supplemental Keywords:

biofuel, rodent behavior, switchgrass

Relevant Websites:

Progress and Final Reports:

  • 2015
  • Final