This chapter reviews the history of and approaches used in studies focused on the effects of contaminants on raptors and raptor populations at the Patuxent Wildlife Research Center (Patuxent) in Laurel, MD. Worldwide raptor declines following World War II were unprecedented and resulted in a sequence of major efforts at Patuxent to understand their cause(s). The peregrine falcon (Falco peregrinus), bald eagle (Haliaeetus leucocephalus), and osprey (Pandion haliaetus) were the species of most concern in North America. Laboratory and field studies at Patuxent complemented each other and yielded timely results of national and international importance, including some findings published in the journals “Science” and “Nature.”

Concern about contaminant effects on wildlife populations came to the forefront during the years immediately following World War II. This concern was worldwide and not limited to one taxonomic group or to personnel and investigations at Patuxent. Contaminant studies of raptors were only part of the story, but this review, with minor exceptions, is limited to raptor studies and the role Patuxent played in this research. Indeed, many important nonraptor contaminant studies done at Patuxent, as well as raptor studies conducted elsewhere, are not mentioned here. For other reviews of contaminant-wildlife issues in the 1950s and 1960s, the reader is referred to “Silent Spring” by Rachel Carson (1962), “Pesticides and the Living Landscape” by Robert Rudd (1964), and “Return of the Peregrine: A North American Saga of Tenacity and Teamwork” by Tom Cade and Bill Burnham (Cade and Burnham, 2003).