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Upper Midwest Environmental Sciences Center
UMESC - Celebrating 50 Years of Science for a Better World - 1959-2009

UMESC Gallery

USGS scientist Tom Custer examines barn swallows near Lake Charles, Lousiana, exposure of barn swallow nestlings to trace elements, petroleum, and PCBs: Full resolution

USGS scientist Tom Custer examines barn swallows near Lake Charles, Lousiana, exposure of barn swallow nestlings to trace elements, petroleum, and PCBs

Photo by Christine Custer, USGS, UMESC, 2003

Usage: This image is public domain/of free use. Please refer to the USGS Copyright section for more details.