The “escalator to extinction”: Climate change causes upslope shifts and mountaintop extirpations in a tropical bird community
Dr Benjamin Freeman1, Micah Scholer1, Dr Viviana Ruiz Gutierrez2, Dr John Fitzpatrick2
1University of British Columbia, Vancouver, Canada, 2Cornell University, Ithaca, United States
Montane species worldwide are shifting upslope in response to recent temperature increases. These upslope shifts are predicted to lead to mountaintop extinctions of species that live only near mountain summits, but empirical examples of populations that have disappeared are sparse. We show that recent warming constitutes an “escalator to extinction” for birds on a remote Peruvian mountain—high elevation species have declined in both range size and abundance, and several previously common mountaintop residents have disappeared from the local community. Our findings support projections that warming will likely drive widespread extirpations and extinctions of high elevation taxa in the tropical Andes. Such climate change-driven mountaintop extirpations may be more likely in the tropics, where temperature appears to exert a stronger control on species’ range limits than in the temperate zone. In contrast, we show that lowland bird species at our study site are expanding in range size as they shift their upper limits upslope, and may thus benefit from climate change.
Biography:
I am a Banting and Biodiversity Research Centre postdoctoral fellow at the University of British Columbiain where I work most closely with Dolph Schluter (PhD from Cornell University). I am an evolutionary ecologist who seeks to understand and explain patterns of biodiversity. I use natural history knowledge to study both classical and cutting-edge issues in niche evolution, species interactions and how species respond to climate change. My research program focuses on three core questions in evolution, ecology and conservation: 1) What factors promote speciation? , 2) What limits species’ geographic distributions? and, 3) How is global climate change impacting biodiversity? I often use montane avifaunas as a model system for these questions.