Data from: Diverse temperate forest bird assemblages demonstrate closer correspondence to plant species composition than vegetation structure

The aggregate structure of vegetation has long provided a strong
conceptual basis for understanding the ecological separation of faunal
species, while correspondence with plant species composition remains
largely underdeveloped and considered secondary to structure. Longstanding
ecological debate on the matter has likely been sustained by statistical
methods incapable of accommodating an entire species composition in the
explanatory role. We used direct ordination methodologies (predictive
co-correspondence and canonical correspondence analyses) that allow the
comparison of prediction levels between composition and structure for
understanding avian assemblage composition in a temperate forestland in
southeastern Ohio. Compositional (birds and woody plants) and structural
(both vertical and horizontal dimensions) data were collected from point
samples comprising a spectrum in topography and successional state. Total
woody plant composition (11.22%) explained more (cross-validatory)
variation in avian species composition than structure, quantified with
dense LiDAR recordings (7.35%) and field methods (6.31%). Plant
composition assumed an integrative character, synthesizing aspects of
environmental condition, structure, and most likely species-specific
preferences for tree and shrub species that structural indices alone could
not for predicting avian species composition. These results conflict with
the traditional view that structure be most influential to avian
assemblage composition. Instead these results demonstrate that plant and
avian assemblages are closely linked, and that plant species per se can be
a powerful tool for predicting avian habitat. More importantly, in
furthering ecological understanding, it is critical to consider the
complex web of interacting processes that make up temperate forest
ecosystems, in which composition occupies a key position.