Survival of Radiocollared Adult Moose in Lower Susitna River Valley, Southcentral Alaska
Modafferi RD and Becker EF. 1997. Survival of Radiocollared Adult Moose in Lower Susitna River Valley, Southcentral Alaska. The Journal of Wildlife Management. 61(2):540-549
Estimates of survival for adult moose (Alces alces) are presented by sex, season, and calendar year (CY) for 204 (66 M, 138 F) radiocollared adult moose monitored from aircraft in lower Susitna River Valley (LSRV) in southcentral Alaska during May 1980 through February 1991. Deaths were attributed to capture problems, hunter kills, defense of human life or property (DHLP), illegal harvest, collisions with trains, and unverified other causes. Capture-related deaths were not included in survival analyses. Hunter kills were mainly censored from survival calculations. Moose were censored from the study for loss of signal contact and shed radiocollars. Summer survival curves did not differ among CYs for females (P = 0.501) or for males (P = 0.819) or among sexes (CYs pooled; P = 0.817). Autumn survival curves did not differ among CYs for females (P = 0.617) or for males (P = 0.617); a difference was detected among sexes (CYs pooled; P < 0.001) with survival higher for females (0.98, SE = 0.007) than for males (0.90, SE = 0.032). We speculate that lower autumn survival in males was from bullet wounding, wounding from rut-related fights with other bull moose, illegal harvest, and fatal encounters with bears. Survival in winter and annual survival varied by sex and CY and was affected largely by mortality associated with accumulation of snow. Given low densities of wolves and no observations of wolf sign at mortality sites we contend that malnutrition was the main cause of mortality in deep snow winters. Nonhunting deaths of male moose in winter was not correlated negatively with hunter kills of males in the previous autumn-early winter. Moose managers should be cognizant of non-hunting mortality of males in autumn and snow conditions through mid-May to evaluate annual survival and to accurately predict size and composition of post-winter populations. Moose management programs should be sufficiently responsive to modify autumn harvest quotas in accordance with survival data collected the previous winter 5 months after autumn post-hunt population surveys.
- Type
- Journal Article
- Authors
- Modafferi, Ronald; Becker, Earl
- Units
- CAKN , DENA , WRST , YUCH
- Keywords
- Alberta , Alces alces, Dynamics, Harvest, Hunting, Moose, Mortality, Populations, Predation, radiotracking, Rates, Snowpack, Survival