The Monarch Butterfly, Milkweeds, and Tropospheric Ozone Air Pollution: A Study of the Potential for Negative Consequences

Objective/Intended Use

Convene a workshop with experts in plant pathology, atmospheric chemistry, and entomology to discuss the effects of ground-level ozone on the interaction between the Monarch butterfly and the milkweed plant. Prepare a synthesis paper of the findings and discussions at the workshop for dissemination to EPA program offices, regional offices, the scientific community, and the general public. Research needs will be articulated in the synthesis paper.

Abstract

The U.S. Environmental Protection Agency's (EPA's) National Center for Environmental Assessment (NCEA) within the Office of Research and Development (ORD) has the responsibility to conduct ecological risk assessments to assess the potential impacts of anthropogenic contaminants in the environment. At an EPA-sponsored workshop plant pathologists and physiologists, biochemists, atmospheric chemists, and entomologists discussed how ozone may be effecting the interaction between the milkweed plant and the monarch butterfly. The monarch butterfly has an eastern and western migratory route. Along both migratory corridors the common milkweed plant is relied upon by the feeding butterfly's larval stage for nutrition. Ozone has been shown to alter the nutritional quality of milkweed and many other plants at concentrations commonly found in ambient air. The scientists plan to develop a synthesis paper that will address the potential for negative consequences to both the plant and the butterfly. The scientists will also take steps toward developing an integrated monitoring network across the U.S. that will begin to provide data on the potential impacts of ozone on the milkweed plant, the insect, and the interactions between the two species.

Project Status

On-going. This study was initiated in the first quarter of FY02. A workshop was convenened in December 2001. The distribution of the milkweed plant in U.S. counties is being compiled in a geographic system software database maintained by the Natural Resource Conservation Service (NRCS) in Baton Rouge, LA. This project is expected to be completed on 3/31/06.

Project Start Date

10/01/2002