SEX-SPECIFIC DYNAMICS OF NORTH AMERICAN ELK IN RELATION TO GLOBAL CLIMATE

• Main Authors: Maier, Julie A. K., Post, Eric
• Format: Article in Journal/Newspaper
• Language: English
• Published: Lakehead University 2001
• Subjects: Raspberry Island; Alces alces; North Atlantic; North Atlantic oscillation; Alaska
• Online Access: http://alcesjournal.org/index.php/alces/article/view/597

The North Atlantic Oscillation (NAO) is a continuous fluctuation in atmospheric mass balance that drives most interannual and decadal variation in winter temperatures and precipitation in the Northern Hemisphere. Effects of the NAO on the population dynamics of red deer (Cervus elaphus) in northern Europe and white-tailed deer (Odocoileus virginianus) and moose (Alces alces) in North America are well documented. In northern Europe, analysis of sex-specific population dynamics in relation to the NAO have documented divergent responses of the sexes to winter warming, but such analysis have been lacking for North American ungulates. We investigated effects of the NAO on the sex-specific population dynamics of Roosevelt elk (Cervus elaphus roosevelti) on Raspberry Island, Alaska, USA. Density of females and of the total population declined after positive (cold and snowy) NAO winters. Density of males was unrelated to the NAO index. Production of young was limited by density of females and increased following positive NAO winters. Hence, in agreement with analyses of the dynamics of red deer in northern Europe, population dynamics of the herd on Raspberry Island related mainly to the influences of winter climate and density on abundance and productivity of females, rather than males.