Sometimes I find, Horace, and I am sure you will agree with this, that you can get too scientific on these things and cause a lot of harm.—CONRAD L. WIRTH to HORACE M. ALBRIGHT, 1956

If the Service is to protect and preserve, it must know what it is protecting, and what it must protect against. It is the function of research to get at the truth, to develop the fund of knowledge necessary for intelligent and effective management.—NATIONAL PARK SERVICE, 1961

After removal of the wildlife biologists to the Fish and Wildlife Service in 1940, nearly a quarter of a century would pass before any meaningful attempt to revitalize the National Park Service's biological science programs. By the early 1960s, the Service would come under public criticism for its weak, floundering scientific efforts, described in one report as "fragmented," without direction, and lacking "continuity, coordination, and depth." [1] Moreover, the Park Service would find its management increasingly challenged by conservation groups, its leadership in national recreation programs seriously weakened, and its control over the parks' backcountry threatened by restrictions in the proposed wilderness legislation, which was gaining support in Congress. These challenges would be mounted in the midst of "Mission 66," the Park Service's billion-dollar program to improve park facilities, increase staffing, and plan for future expansion of the system—a highly touted effort to enhance recreational tourism in the parks, and so named because it was to conclude in 1966, the Service's fiftieth-anniversary year.

From 1940 through 1963, national park management was dominated by two directors: Newton Drury, who succeeded Arno Cammerer in August 1940 and resigned in March 1951; and Conrad Wirth, who served from December 1951 to January 1964. (Between Drury and Wirth fell the brief, eight-month directorship of Arthur Demaray, whose preretirement appointment was in recognition of his lengthy and competent service as associate director.) The Drury-Wirth era was marked by the strikingly different personalities and philosophies of these two leaders: Drury, the conservative who criticized Park Service expansion and development in the 1930s, then provided more than a decade of cautious leadership; and Wirth, the highly effective entrepreneurial promoter and developer of the national park system.

Newton Drury was the first director not to have had prior experience in national park management. His principal conservation work had been as executive director of the Save the Redwoods League from late 1919 until he resigned in 1940 to become Park Service director. [2] As the Redwoods League had focused on California issues, Drury's contacts were mainly in that state; he lacked experience in dealing with Congress and the Washington bureaucracy. His personal conservatism was reflected in his loyalty to the Republican Party (which appears not to have been an obstacle to his appointment in the Roosevelt administration) and in his leadership of the Service. Drury believed that the national parks should be limited primarily to the nation's premier scenic landscapes. He took a slow, deliberate approach to improving administrative and tourism facilities in the parks. And he was not enthusiastic about involvement with reservoir recreation management or with the national recreation assistance programs begun during the New Deal. [3] Clearly, Drury did not fit the mold of the previous directors, who enthusiastically boosted park development and expansion of Service programs.