Pied flycatcher numbers are crashing in places where climate change has knocked the birds' spring migration out of sync with the food bonanza on the breeding ground.
That's the conclusion from a study of nine breeding areas in the Netherlands, says Christiaan Both of the Netherlands Institute of Ecology in Heteren. Each spring, the pied flycatchers arrive there after traveling 4,500 kilometers from Africa, cued mostly by day length.
Unfortunately for these birds, late-April weather in the Netherlands has warmed some 4°C during the past 20 years. In some places, that warmth has moved up the timing of a short-lived banquet of caterpillars, which adult flycatchers feed