Bioeconomics of an Invasive Species: The Gypsy Moth

Project Director
Conrad, J. M.

Recipient Organization
CORNELL UNIVERSITY
(N/A)
ITHACA,NY 14853

Performing Department
APPLIED ECONOMICS & MANAGEMENT

Non Technical Summary
The gypsy moth is perhaps the most studied invasive species in the United States. Since 1869, the gypsy moth has spread from Boston west to Wisconsin, southwest to Kentucky, and south to North Carolina. The first gypsy moth outbreaks in New York State occurred in the 1960s. It is estimated that partial defoliation occurs on more that 1,000,000 acres each year. While there is a large biological literature on the gypsy moth, the economic literature is limited, and there has been no recent attempt to integrate the economics of control cost and defoliation damage with the dynamics and diffusion of the gypsy moth. The willingness to pay suvey will allow us to estimate damage functions which, in turn, will allow the development of bioeconomic models that may be used to assess the value of (a) control of established populations and (b) slowing the spread.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
605	0620	1130	30%
605	0620	3010	70%

Knowledge Area
605 - Natural Resource and Environmental Economics;

Subject Of Investigation
0620 - Broadleaf forests of the North;

Field Of Science
1130 - Entomology and acarology; 3010 - Economics;

Keywords

Goals / Objectives
To survey urban, suburban, and rural property owners in the Northeastern U.S. to determine their willingness to pay to reduce defoliation caused by the gypsy moth caterpillar. This information will be used with a spatial-dynamic bioeconomic model to determine the value of programs to reduce population levels where the gypsy moth is already established and to slow its spread to the Midwest and Southeastern U.S.. The outputs of this project will include descriptive statistics of the willingness to pay to reduce defoliation by region and property type (urban, suburban, rural) and an econometric analysis that bounds willingness to pay and estimates a damage function for percent defoliation.

Project Methods
The survey will be conducted online at a Cornell University web site. The survey will collect information on (a) the respondent's household, (b) the location and characteristics of the property (including number and types of trees on the property), (c) the respondent's previous experience with gypsy moth catterpillars and defoliation, and (d) the respondent's willingness to pay to reduce the level of defoliation in the next outbreak.

Progress 10/01/08 to 10/01/09

Outputs
OUTPUTS: The gypsy moth (Lymantria dispar) is an invasive species introduced into North America in 1868 or 1869. The population undergoes episodic outbreaks. At peak population levels, gypsy moth caterpillars can severely defoliate deciduous trees, such as those found in the eastern U.S. and Canada. The paper, Bioeconomics Meets Biocomplexity: The Gypsy Moth, was completed and submitted to the Journal of Environmental Economics and Management. This paper identifies the optimal threshold to apply a Bt spray or the fungus E. maimaiga to control the gypsy moth in areas where it is established. The optimal threshold is the one that minimizes the discounted sum of control coats and defoliation damage. In the base-case parameter set the optimal threshold to apply the Bt spray was 450 egg masses per acre while the optimal threshold when using E maimaiga was 400 egg masses per acre. A second paper is currently being written. This paper will estimate the economic value of optimally slowing the spread of the gypsy moth. A spatial-dynamic (diffusion) model will be used to identify the best threshold to apply a Bt spray or the fungus E. maimaiga so as to minimize the discounted value of control costs and defoliation damage over the potential range of the gypsy moth in the U.S. PARTICIPANTS: Jon Conrad and Xi Yang (Department of Applied Economics and Management, Cornell University). TARGET AUDIENCES: Resource economists, entomologists, and state and federal agencies charged with managing the gypsy moth. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The two bioeconomic models developed during this project will provide estimates of the value of controlling the gypsy moth population and might be applied to other forest defoliators.

Publications

No publications reported this period