Coping with Uncertainty in Wildlife Biology

A decade after Romesburg admonished wildlife biologists to establish and test hypotheses to gain more "reliable knowledge," we have added an incentive to bring rigor to our science. Wildlife biologists are finding themselves defending their science against often savage criticism. At least 2 factors are central to producing solid, defendable science: (1) the rigorous application of scientific methods and (2) the development of clear operational definitions for terminology. The hypothetico-deductive (H-D) process, in the form of statistical tests of hypotheses based on experimental data, is hailed as the superior means of acquiring strong inference and reliable knowledge. Results from experimental studies, however, are seldom available, and most management decisions are made on the basis of incomplete information. We argue that even in the absence of experimental information, the H-D process can and should be used. All management plans and conservation strategies have properties that can be stated as falsifiable hypotheses and can be subjected to testing with empirical information and with predictions from ecological theory and population simulation models. The development of explicit operational definitions for key concepts used in wildlife scienceparticularly terms that recur in legislation, standards, and guidelines-is a necessary accompaniment. Conservation management and planning schemes based on the H-D process and framed with unequivocal terminology will allow us to produce wildlife science that a credible, defendable, and reliable. J. WILDL. MANAGE. 55(4):773-782 Wildlife biologists face a new and exceedingly challenging era. No longer is wildlife science a lonely enterprise carried out on distant landscapes. No longer do wildlife biologists write on natural histories and population trends for an audience consisting only of other wildlife boilogists. And, no longer are the results of wildlife studies relegated to moldering stacks in specialty libraries. In just a few short years wildlife biologists have been swept up into public debates and taken from the status of sequestered experts to that of key players. Wildlife biologists and their colleagues in forestry, range sciences, and conservation biology have been drawn into the J. Wildl. Manage. 55(4):1991 SCIENCE AND WILDLIFE MANAGEMENT • Sinclair 773 SCHOENER, T. W. 1986. Mechanistic approaches to community ecology: a new reductionism? Am. Zool. 26:81-106. SCHULLERY, P. 1989. The fires and fire policy. BioScience 39:686-694. SINCLAIR, A. R. E. 1977. The African Buffalo. Univ. Chicago Press, Ill. 355pp. , 1979. Dynamics of the Serengeti ecosystem: process and pattern. Pages 1-30 in A. R. E. Sinclair and M. Norton-Griffiths, eds. Serengeti: dynamics of an ecosystem. Univ. Chicago Press, Ill. , 1981. Environmental carrying capacity and the evidence for overabundance. 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Evaluation of the range condition concept. Rangelands 1:52-54. SMUTS, G. L. 1978. Interrelations between predators, prey and their environment. BioScience 28:, 316-320. WALTERS, C. 1986. Adaptive management of renewable resources. MacMillan, New York, N.Y. 374pp. WATT, K. E. F. 1968. Ecology and resource management. McGraw-Hill, New York, N.Y. 450pp. Received 24 April 1991. Accepted 2 July 1991. Associate Editor: Morrison. 774 UNCERTAINTY IN WILDLIFE BIOLOGY Murphy and Noon J. Wildl. Manage. 55(4):1991 land-use decision-making process and have been required to defend the merits of their field studies in a heretofore foreign venue. Land use policy has become big news-with big economic consequences and even bigger political stakes. Environmental organizations have filed appeals of virtually every National Forest Plan that has been completed in the past several years. Management plans for populations of bison (Bison bison) and elk (Cervus elaphus) that migrate through Yellowstone National Park have been challenged in federal courts by hunters and those with livestock interests. Congress commissioned a rare cooperative effort among the U.S. Forest Service, U.S. Fish and Wildlife Service, Bureau of Land Management, and National Park Service that produced a plan to save the threatened northern spotted owl (Strix occidentalis). The list goes on. In an increasingly litigious society, even wilderness is not free of contention or beyond the reach of the courtroom. We may not welcome them, but lawyers are joining us in the stacks of our biology libraries. Now, a decade after Romesburg (1981) admonished us to establish and test hypotheses to gain more "reliable knowledge," that is, to do better wildlife biology, we have an added incentive to bring rigor to our science. Wildlife biologists are finding themselves defending their science against often savage criticism. Our definitions of "threatened" and "endangered," our monitoring data, our population estimates, our inferences regarding the decline of native populations will be scrutinized by the timber industry, livestock associations, mining interests, environmental organizations, and other interest groups with particular policy agendas. These groups will employ lawyers and consultant scientists to seek flaws and weaknesses in our definitions, our analyses, and our products. And in those cases in which no obvious flaws exist, critics will note how little we actually know. They will exaggerate and misconstrue the inherent, inevitable uncertainty that accompanies our best