Climate change is implicated in poleward shifts in the distributions of species

"Climate change is expected to result in climatic zones moving poleward and an associated shift in the geographic ranges of bird species. Evidence for such shifts is now becoming apparent. It remains difficult to causally link such distributional shifts specifically to climate change as a wide range of additional factors also influence species distributions. However, thanks to recent research in Europe and North America, a remarkably consistent pattern is emerging that provides compelling evidence that climate change is responsible for significant northward shifts in the distribution of avian communities across the northern hemisphere."  See:
http://www.birdlife.org/datazone/sowb/casestudy/171

Read more at these links

Projected Impacts of Climate and Land-Use Change on the Global Diversity of Birds: http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0050157#pbio-0050157-g003

Climate change is already documented as having impacted many bird species

http://www.birdlife.org/datazone/sowb/casestudy/287

And a related new paper -"Range-Wide Latitudinal and Elevational Temperature Gradients for the World's Terrestrial Birds: Implications under Global Climate Change" --- can be found at

: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0098361