A variation on the white-throated sparrow’s song spread 3,300 kilometers in just a few decades
Some North American birds are changing their tune.The traditional song of the white-throated sparrow (Zonotrichia albicollis) ends with a repeated triplet of notes. By 2000, however, some birds in western Canada were whistling a variation ending in a two-note pattern
The findings fly in the face of previous hypotheses that birdsong dialects don’t change much within local regions. The rapid spread of the new song is akin to someone moving from Kentucky to Vancouver and everyone in Vancouver suddenly picking up a Kentucky accent, says Ken Otter, an avian behavioral ecologist at the University of Northern British Columbia in Prince George, Canada.
Otter and his colleagues documented the adoption of the western song at a research station in eastern Canada. In 2005, only one male out of 76 surveyed sang the doublet-ending song. In 2014, 22 percent of 101 males surveyed sang the new song. And in 2017, nearly half of 92 males recorded had adopted the variation.
