Good Day Streetlight
Study reveals American robins start singing hours earlier than they normally would in areas with extensive light pollution
THE DARKEST HOUR is just before dawn—or so goes the old saying. But try telling that to the robins living in some of the most brightly lit urban areas in the country, including the grounds of the White House. According to a study by University of Florida researcher Mark Miller, American robins—which normally start singing right around sunrise—start singing hours earlier in areas with extensive light pollution.
During his late-night and early-morning observations, Miller visited robin habitats from rural Pennsylvania to the well-lighted heart of Washington, D.C. In the most urban areas, says Miller, “they were singing two hours and forty-five minutes earlier than in the darkest areas.”
Miller says that there are obvious downsides to the birds’ early-morning chorus, including an increased risk of predation. But early activity could also mean more hours in which to forage for food. “There needs to be more study,” he says.—Hannah Schardt