Site fidelity and seasonal range use by bighorn rams

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Abstract
The seasonal dispersion of Rocky Mountain bighorn rams (Ovis canadensis canadensis) in southwestern Alberta was monitored over 5 years. Rams captured on a 10-km2 low-elevation range (a wildlife sanctuary) were relocated up to 48 km away. Numbers of rams in the sanctuary peaked in early June and in October. About 40–50 rams wintered in the wildlife sanctuary and in areas to the east, and for the two concentrations they were joined by nonresident rams, particularly in early June. Site fidelity of resident rams was > 98% for the two concentrations, 77% for the rut, and 62% for the summer. Younger rams were less migratory than mature rams. Exploitation of areas east of the sanctuary likely allowed early access to new growth forage, but rams did not consistently exploit the entire altitudinal range available to them. Individual rams had different seasonal dispersion patterns, and these were not rigidly repeated in successive years. It is suggested that gregariousness had a major role in determining distribution, and that the two concentrations may allow practice and development of social skills.