Moose, Alces alces, Habitat Relative to Riparian Succession in the Boreal Forest, Susitna River, Alaska

We documented Moose, Alces alces, habitat characteristics relative to boreal forest succession in the Susitna River flood­ plain, Alaska. Early Shrub and Old Poplar (Populus balsamifera) Forest sites were most important to wintering Moose. Browse availability was the principal factor affecting winter habitat selection by Moose. Feltleaf Willow (Salix alaxensis) in Early Shrub was the principal browse species, producing approximately I 0 I kg/ha of browse. In a year of average snow­ fall, 76% of available Feltleaf Willow was utilized. Other important species, High Bushcranberry (Viburnum edule) and Rose (Rosa acicularis) were abundant in Old Poplar Forest and Birch-Spruce (Betula papyrifera-Picea glauca) Forest, but were unavailable when snow exceeded approximately I I 0 cm. Non-vegetated sites, dry sloughs and frozen river channels had significantly less (p < 0.05) snow accumulation than other sites, making them preferred paths of access during periods of deep snow. Wind speed did not vary significantly (p < 0.05) between successional stages older than Early Shrub, and wind did not appear to affect habitat use. Moose exhibited some preference for cover during periods of rest, especially dur­ ing warm sunny days in late winter. While biologically feasible, enhancement of browse production in the Susitna River floodplain appears logistically impractical and of wrong priority. Habitat enhancement should be focused on upland sites where fire suppression has altered natural ecosystem functions, not in floodplain where the river continues to maintain a constant supply and diversity of successional conditions important to Moose and other wildlife.