Habitat relationships of wintering passerines in the River of No Return Wilderness Area of central Idaho

Populations of wintering passerine birds and vegetation structural attributes were sampled in five vegetation types within the Big Creek Drainage, River of No Return Wilderness Area (now the Frank Church River of No Return Wilderness Area), central Idaho, in 1980 and 1981. Species occurrence differed between the two years. Most species used two or more vegetation types, with forested habitats receiving more use than open habitats. Stepwise discriminant analysis identified which of 21 vegetation variables were associated with presence or absence of bird species. Good supply may require birds to be opportunistic in their use of habitats in winter, and this opportunism may be reflected in the patterns observed in the Big Creek Drainage.