Bird communities and vegetation associations across a treeline ecotone in the Mealy Mountains, Labrador, an understudied part of the Boreal forest

• Main Authors: Lewis, Keith P., Starzomski, Brian
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: NRC Research Press (a division of Canadian Science Publishing) 2015
• Subjects: Arctic; Canada; Mealy Mountains; Climate change; Tundra
• Online Access: http://hdl.handle.net/1807/69123; http://www.nrcresearchpress.com/doi/abs/10.1139/cjz-2014-0309

We examined the factors structuring bird communities across a complex sub-arctic treeline in the Mealy Mountains, Labrador, Canada. Using point counts of bird abundance in 2007 and 2008, we show that changes in vegetation driven by elevation are strongly correlated with avian community structure in this treeline ecotone system. Overall, avian diversity was higher in the forest compared to other habitat classes (krummholz, deciduous shrub, and alpine). There were strong correlations between avian diversity and vegetation richness as well as structure among and within habitat class in 2008. Numerous habitat types (subset of habitat class) were correlated with avian composition although some species were clearly habitat generalists. Contrary to expectation, avian species composition was associated with physiognomy (vegetation structure) in alpine and deciduous shrub, and with neither physiognomy or floristics (vegetation species composition) in krummholz and forest. Given the strong impact of elevation on vegetation and the demonstrated influence on bird communities, we note that for bird species whose near-southernmost populations are found in the Mealy Mountains, climate change is likely to have a strong negative effect if alpine tundra habitat is lost. Further, forest bird species are likely to benefit from the increased tree cover as treeline moves poleward and upward. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.