The butterfly season in the Netherlands began about three weeks earlier than normal due to record high spring temperatures. Migratory birds that breed in the Netherlands will hatch their chicks too late to feed on caterpillars, and may suffer from lack of suitable food.
Information about the butterfly situation was published by a group from the Wageningen University that prepares a Nature Calendar each year. The calendar is used to report the progress of certain species.
Migratory birds like wheatears, cuckoos and swallows rely on abundant supplies of caterpillars each spring to feed their young. Most baby birds will hatch too late this year, after the caterpillars have already become butterflies.
Source: Jonge vogels missen rupsen
