Over 290 species of birds have been seen at Fermilab including several endangered species. The diversity of habitats to be found on the 6,800 acre site make it a favorite location for birdwatchers in Chicago’s western suburbs.
The laboratory has been a haven for naturalists and ecologists since at least the 1970s, when Professor Robert Betz of Northeastern Illinois University began leading a project to restore Fermilab's prairie land. Volunteers, including lab and local park district staffers and nature enthusiasts on and off site, formed the Ecological Land Management Committee to promote the restoration of the lab's tall-grass prairie. Later its scope expanded to embrace Fermilab's woodlands, savannah, and other ecosystems.
Peter Kasper has been keeping weekly records of all bird species seen on site since 1987. He was later joined by Denis Kania and Dave Spleha. When Fermilab became a National Environmental Research Park (NERP) in 1989, the bird survey became one of the NERP projects. The bird monitoring is now part of the wildlife monitoring done by volunteers with the non-profit organization Fermilab Natural Areas