Dynamics of moose populations in the AOSERP study area in northeastern Alberta

• Main Authors: Keith, L. B., Hauge, T. M.
• Format: Other/Unknown Material
• Language: English
• Published: 1980
• Subjects: geo; envir; Birch Mountains; Firebag River; Alces alces
• Online Access: https://doi.org/10.7939/R3J960H4V; https://era.library.ualberta.ca/items/86e9df2b-24e2-43f9-aef1-cccf6a6bb687

Intensive studies of moose were conducted on a 25 000 km study area in northeastern Alberta from January 1976 to June 1978. Sixty-six moose (Alces alces) were radio-collared and another eight were colour-marked only. The population is either stationary or slowly declining. An estimate of 4595 (0.18/km2) for the entire study area was obtained in the winter of 1977-78. Moose were largely absent in winter from the Birch Mountains and the jack pine area north of the Firebag River. There was a significant increase in the proportion of yearlings in the population between the winters of 1975-76, as a result of higher reproduction and/or calf survival in 1975-76. Our best estimate of the combined yearling and adult sex ratio was 30:70. There was a significant inverse relationship (r2 = 0.62) between age of radio-collared bulls and dates of antler drop. Seasonal shifts between winter and summer home ranges were made by 34 (76%) of 45 moose; 13 (38%) of these movements exceeded 20 km. No significant differences in home-range size were found between sexes and seasons. Three distinct periods of increased movement among bulls were observed; April-May, September-October, and December-January. Cow movements were more leisurely and less well-defined. Spring (May-June) calf-cow ratios among radio-collared cows >3 years old averaged 88:100. Calf production as indexed by calf-cow ratios was similar in spring (May-June) 1976 and 1978, but autumn ratios were higher in 1977 than 1976. Calves constituted 30% of the winter populations in 1975-76, 18% in 1976-77, and 20% in 1977-78. The annual survival rate of calves of radio-collared cows was 0.27. Survival of these calves was lowest in the first month of life (0.61) and rose in subsequent months (0.95). An estimated 29% of calf losses were due to wolf predation. The annual survival rate of radio-collared yearlings and adults averaged 0.75. A second estimate of 0.76 to 0.77 was obtained independently from demographic and kill data for the entire study area population in 1977-78. ...