Sonja Birthisel, Master of Science in Ecology and Environmental Sciences, Receives Grant from Maine Agricultural and Forest Experiment Station

Posted October 15, 2013

Sonja Birthisel studies how both weeds and weed seed predators affect farming in Maine. A Master student in Ecology and Environmental Sciences, Birthisel works under UMaine’s School of Food and Agriculture to study how local environments influence weed seed predators and the activity and density of particular species. Using a 10 acre organic farm in Dixmont, Maine Birthisel established a 20 meter grid and conducted pitfall trapping to characterize the invertebrate community, and seed feeding assays, with and without invertebrate exclosures. Her results show that habitat features such as vegetative cover and presence of key plant species are more important regulators of seed predation than spatial orientation. Her work led to the development of a method to measure second-order predation of invertebrate seed predators, and to conducting work investigating the effect foodweb dynamics may play in regulating seed predation. This work led to a grant from Maine Agricultural and Forest Experiment Station. Sonja’s results have also been accepted into the publication Biological Control and she has presented her research at the national meetings of the Ecological Society of America and the Weed Science Society of America.