Are temperate mixedwood forests perceived by birds as a distinct forest type?

Forestry practices used in mixedwood forests have led to a reduction of the availability of mixedwood stands and to a simplification of the forest mosaic, with unknown consequences on wildlife. We assessed bird occurrences at different spatial scales (50-, 100-, and 1000-m radius) in response to coniferous, deciduous, and mixedwood stands within the Quebec balsam fir – yellow birch domain. Our objective was to evaluate whether birds perceive temperate mixedwood forests as distinct from deciduous and coniferous forests. We quantified bird occurrence at 57 observation points and determined habitat composition from forest maps. At the 50-, 100-, and 1000-m scales, the occurrence of two, four, and four species, respectively, was positively related to mixedwood stands. Among them the Blackburnian Warbler, the Northern Parula, the Black-throated Blue Warbler, and the Ovenbird responded at more than one scale. Some species were also influenced by coniferous and deciduous stands at the three spatial scales. Mixedwood stands were positively associated with the occurrence of many species and moreover were preferred over coniferous or deciduous stands by some species. These results support our hypothesis that mixedwood forests are distinct habitats and provide a new justification for preserving this forest type.