Temperature-associated dynamics of songbird winter distributions and abundances

Ambio. 2007 Dec;36(8):657-60. doi: 10.1579/0044-7447(2007)36[657:tdoswd]2.0.co;2.


Using Christmas Bird Count data, we analyze the annual spatio-temporal abundances of six passerine species in the upper Great Plains, US (1960-1990). This study provides new insight into how global warming could cause separation of species within present-day communities. We find that winter relative abundances of similarly-sized songbirds are differentially affected by ambient winter temperature. As such, average annual winter temperature fluctuations (i.e., severity of winter) are significantly (P < 0.05) correlated with the relative abundances of three species while the other three are not. Our conditional probability-of-occurrence analysis indicates that the abundances of the three temperature-associated species declined markedly below -4 degrees C while the abundances of the other three species fluctuated little from 8 degrees C to -16 degrees C. We conclude that even in colder climates i) the winter distributions of some, but not all, songbirds are directly or indirectly limited by temperature; and ii) these birds have dynamic abundances that can quickly respond to temperature changes.

MeSH terms

  • Animals
  • Greenhouse Effect*
  • Population Density
  • Population Dynamics
  • Seasons
  • Songbirds*
  • Temperature
  • United States