Recipient Organization
UNIVERSITY OF CALIFORNIA, DAVIS
410 MRAK HALL
DAVIS,CA 95616-8671
Performing Department
Evolution and Ecology
Non Technical Summary
This project supports the mission of the Agricultural Experiment Station by addressing the Hatch Act area(s) of: plant and animal production, protection, and health; multiple use of forest rangelands, and urban forestry; sustainable agriculture.The European Paper Wasp (EPW) is an invasive insect recently naturalized in California; as a major predator of caterpillars it has potential positive impacts on plant protection, urban forestry, and sustainable agriculture. It simultaneously poses a threat to butterfly faunas, including endangered species, and to other predators on caterpillars, particularly birds. By using a pre-existing butterfly-monitoring program, this project aims for the first time to identify and quantify EPW impacts on butterflies. These finding will carry implications for agriculture and horticulture as well as butterfly conservation. It should be noted that because regional butterfly faunas are declining due to climate, land use changes, and pesticides, it is important to separate out any EPW contributions to this decline.
Animal Health Component
(N/A)
Research Effort Categories
Basic
100%
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
The European Paper Wasp Polistes dominula (Hymenoptera, Vespidae) (EPW) is a recently-nautralized predator of caterpillars. In other areas of North America it has reputedly caused catastrophic declines in Lepidopteran populations, particularly in urban and suburban areas. This project aims to quantify its impacts on butterfly populations and species diversity in north-central California, utlizing a pre-existing series of permanent monitoring sites (established between 1972 and 1988). Its presence and approximate date of arrival at these sites are well-documented. Because regional butterfly faunas are in broad decline, one specific goal is to identify the role of the EPW in these declines.
Project Methods
The Project Director's monitoring program is described in detail at http://butterfly.ucdavis.edu. Sites are visited biweekly during butterfly season. Butterflies, EPW and native Polistes are censused using the Pollard Walk method. Data are analyzed retrospectively using a variet of multivariate methods to separate potential impacts of climate, land use, pesticides and EPW as factors contributing to generalized butterly decline.