GEOGRAPHICAL VARIATION IN THE MATING AND CALVING PERIODS OF MOOSE

Abstract

In some ungulates, variations in the timing of mating and calving periods are related to environmental conditions. It has been suggested that such an adjustment of the timing of reproductive events to local conditions would maximise calf survival as the calf benefits from abundant high quality forage during the early stages of lactation. Published data were analyzed to assess the existence of temporal variations in reproductive events for moose (Alces alces). Dates corresponding to mating (n = 19) and calving (n = 18) periods (median, beginning, end, and duration) were correlated to latitude, longitude and climatic parameters (temperature, precipitation, timing of the growing season) obtained from weather stations. Most mating occurred over a 15-day period, form 23 September to 8 October. Most births were recorded over 19 days, between 19 May and 8 June. The only significant correlation found (P < 0.01) relates the beginning of the mating period to mean total snowfall. Results suggest that variations in the timing of the reproductive events among moose populations are weak and independent from the influence of environmental conditions. Comparisons with other species suggest that the low variability in environmental conditions encountered by the populations studied could, in part, explain this finding.