Northern Alaska oil fields and caribou

Caribou (Rangifer tarandus) are a prominent factor in regulating and managi ng oil and gas exploration and development in Alaska. Concerns that the oil fields in the Prudhoe Bay region of northern Alaska have negatively affect ed the distribution and productivity of the Central Arctic caribou herd (CA H) have been expressed in scientific literature and management documents su ch as environmental impact statements. The number of CAH caribou in the wes tern summer range that includes the oil fields declined by more than 50% be tween 1992 and 1995 but then almost doubled between 1995 and 1997. Numbers of caribou in the eastern portion of the range, without oil fields, showed opposite trends during these time intervals. The changes in numbers of cari bou in areas with and without oil fields are probably due to movements betw een summer ranges rather than oil-field impacts. Although there may be some disturbance of animals in the oil fields, population-level impacts apparen tly have not occurred. The number of caribou in the CAH has increased from approximately 5,000 to approximately 20,000 since oil-field development beg an, and the management objectives for the CAH have been met despite develop ment of the largest oil and gas fields in the United States. Managers and r egulators should acknowledge that coexistence of caribou with oil and gas d evelopment demonstrates the success of mitigation, regulation, and manageme nt efforts, These successes should be cited and incorporated in planning ef forts for future oil development and in public management documents such as environmental impact statements (EIS), Management documents can be conside red as scientific and objective only if all available information is includ ed, regardless of whether the information has negative or positive connotat ions for developments.