Wolf Predation on the Nelchina Caribou Herd: A Comment
Van Ballenberghe V. 1989. Wolf Predation on the Nelchina Caribou Herd: A Comment. The Journal of Wildlife Management. 53(1):243-250
I review data, analyses, and conclusions of Van Ballenberghe (1985) and Bergerud and Ballard (1988) on the population dynamics of the Nelchina caribou (Rangifer tarandus) herd of southcentral Alaska to clarify differing interpretations. Correlation and regression analyses failed to discriminate between hypotheses of winter severity versus predation as primary limiting factors of this herd during its decline or to clarify the role of wolf (Canis lupus) predation in triggering the herd's eruption or contributing to its increase after the decline. Data on caribou numbers, wolf numbers, and caribou recruitment lacked sufficient accuracy and precision for statistical analyses and correlations yielded different results depending on choice of variables. Empirical observations of the Nelchina herd and 3 adjacent herds indicated that caribou in multiprey systems increased when an index of prey biomass/wolf exceeded 200, an equilibrium point above which wolves were swamped by abundant prey. Biomass indices for the Nelchina herd during 1950-85 ranged from 309 to 2,178, suggesting that wolf predation played a minor role in the population dynamics of this herd.
- Type
- Journal Article
- Authors
- Van Ballenberghe, V
- Units
- DENA
- Keywords
- Denali National Park And Preserve, Mount Mckinley National Park, Mt. McKinley National Park