Alaskan Trumpeter Swans in a Warming World
Schmidt, J.H., Lindberg, M.S., Johnson, D.S., Conant, B. and King, J. 2009. Evidence of Alaskan trumpeter swan population growth using Bayesian hierarchical models. Journal of Wildlife Management 73: 720-727.
Results indicated that "adult swan populations in Alaska increased at an average rate of 5.9% annually and cygnet production increased at 5.3% annually." The authors also found that "cygnet production exhibited higher rates of increase at higher latitudes in later years," which they opined was "a response to warmer spring temperatures."
Given such findings, the five researchers concluded that "trumpeter swan populations are increasing in Alaska, especially at northern latitudes," stating that their study "represents one of the first to demonstrate a shift in breeding range of a bird possibly due to climate change." Hence, "for trumpeter swans," they say "it appears that breeding range limits in Alaska have expanded," in response to the significant warming experienced there between 1968 and 2005, suggesting once again that warmer is better than colder for earth's biosphere.