Saturday, August 09, 2008

Birds Moving North

Poster child for climate change?

Photo by
Henry McLin

Will over at The Nightjar has been writing about some of the findings from the newly revised breeding bird atlas from New York state, starting with nightjars. Breeding bird altases, when repeated at 10-20 year intervals, can provide snapshots of how individual species are faring over time. They can also provide a means for assessing large-scale changes in a region's bird populations. Some researchers at SUNY College of Environmental Science and Forestry used the data to study how 83 species were responding to climate change. Many birds are moving their ranges farther north, and both the northern and southern range boundaries are shifting.
“They are indeed moving northward in their range boundaries,” said researcher Benjamin Zuckerberg, whose Ph.D. dissertation included the study. “But the real signal came out with some of the northerly species that are more common in Canada and the northern part of the U.S. Their southern range boundaries are actually moving northward as well, at a much faster clip.”

Among the species moving north are the Nashville warbler, a little bird with a yellow belly and a loudly musical two-part song, and the pine siskin, a common finch that resembles a sparrow. Both birds have traditionally been seen in Northern New York but are showing significant retractions in their southern range boundaries, Zuckerberg said.

Birds moving north from more southern areas include the red-bellied woodpecker, considered the most common woodpecker in the Southeastern United States, and the Carolina wren, whose “teakettle, teakettle, teakettle” song is surprisingly loud for a bird that weighs less than an ounce.
The linked article states that New York is the only state to complete two breeding bird atlases. This is not quite correct, as Maryland and DC have also completed their second atlas, or at least the censusing phase. The data is available, though the book is not published.