Species-specific population dynamics of cervids in a multipredator ecosystem

In response to the natural experiment created by gray wolf (Canis lupus) re colonization of the Glacier National Park area, from 1990 to 1996 we examin ed population trends and female survival rates of white-tailed deer (Odocoi leus virginianus), elk (Cervus elaphus), and moose (Alccs alccs) preyed upo n by wolves, cougars (Puma concolor), bears (Ursus spp.), coyotes (Canis la trans), and humans. The effects of the complete suite of native large carni vores on prey have not been previously reported. Annual survival rates were 0.74 for 64 deer. 0.83 for 53 elk, and 0.88 for 47 moose, Cougars and wolv es were the most significant sources of mortality for deer (0.09 and 0.06 r espective annual cause-specific mortality rates) and elk (0.06 and 0.03 res pective annual cause-specific mortality rates), and wolves and bears were t he most significant sources of mortality for moose (0.03 and 0.04 respectiv e annual cause-specific mortality rates). All age classes of deer were rela tively equally vulnerable to predators, while young and old moose and elk w ere most vulnerable. Moose survival al rates were higher where wolves were absent and where white-tailed deer were present. Deer and elk populations d eclined as wolf numbers increased (lambda = 1.20). The moose population rem ained relatively stable. Predation appeared to be the primary factor limiti ng growth of deer and elk populations in this system. Predator-prey manager s need to carefully monitor prey populations in areas wolves recognize. Man agers may be able to manipulate alternative prey densities to enhance prey populations that are affected by wolves, cougars, and bears.