Avian assemblages in natural and second-growth balsam fir forests in Western Newfoundland

Avian assemblages were investigated in natural (uncut) and mature second-growth balsam fir (Abies balsamea) forests in western Newfoundland. Within these forest classes, there were four forest types varying in site richness. Birds were studied to determine if assemblages differed between forest clas...

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Bibliographic Details
Main Author: Hogan, Holly A.
Format: Thesis
Language:English
Published: Memorial University of Newfoundland 1997
Subjects:
Online Access:https://research.library.mun.ca/10669/
https://research.library.mun.ca/10669/1/Hogan_HollyAnn.pdf
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Summary:Avian assemblages were investigated in natural (uncut) and mature second-growth balsam fir (Abies balsamea) forests in western Newfoundland. Within these forest classes, there were four forest types varying in site richness. Birds were studied to determine if assemblages differed between forest classes and among forest types, and to determine if differences in avian assemblages were associated with vegetation structure and composition. The IPA (lndice Ponctuel d'Abondance) version of the point-count method was used to census birds. -- The result indicated avian species richness, diversity and total abundance (IPA) did not differ between natural growth and second growth forest. Three species were more abundant in natural growth. Black-backed Woodpeckers (Picoides arcticus) were found exclusively in natural growth. Five species and one guild (seed-eating) were more abundant in second growth forests. -- A trend toward increased abundance with increased forest type richness was evident for Black-throated Green Warbler (Dendroica virens), Ovenbird (Seiurus aurocapillus) and Mourning Warblers (Oporomis philadelphia) and the seed-eating guild as well as for species richness and IPA. The foliage-gleaning guild was least abundant in moss forest types, where foliage height diversity and habitat diversity (Shannon-Wiener index) were lowest. -- Twelve bird species and three guilds had significant multiple regression models in the analyses using principal components from analyses of vegetation variables from all stands. Of these, Black-backed Woodpecker, Yellow-bellied Flycatcher (Empidonax minimus) and Yellow-romped Warbler (Dendroica coronata) and the flycatching guild were indicated to avoid dense fir with canopy cover and snags (PC1), while Boreal Chickadees (Parus hudsonicus) and Black-throated Green Warbler, and the generalists guild preferred such areas. Seven species and two guilds (foliage-gleaning and generalists) strongly preferred rich forests with ferns, and forbs (PC2). Seven species and one guild (flycatching) ...