Effects of Wind-Hardened Snow on Foraging by Reindeer (<i>Rangifer Tarandus</i>)

  • W.B. Collins
  • T.S. Smith
Keywords: Animal behaviour, Animal food, Craters, Reindeer, Snow, Surface properties, Thickness, Tundra ecology, Winds, Seward Peninsula, Alaska


Various methods were investigated for assessing the relationship between wind-hardened snow (upsik) and forage availability to reindeer. Mean bottom area of individual craters was not a function of depth, hardness or integrated hardness. Individual crater area was partially dependent on specific cratering time (r2 = .60). Cratering time per active period increased with integrated snow hardness (r2 = .88). Number of craters and total area cratered increased with decreasing site hardness. Reindeer always cratered microsites of lesser depth and hardness than found in the general feeding site. A threefold decrease in snow hardness resulted in a fourfold increase in forage availability.

Key words: Rangifer, snow hardness, snow depth, forage availability