Changing Climate Leaves Migrating Bird Behind

Changes in the Earth’s climate may be especially difficult for migratory birds to adapt to, scientists report in last Thursday’s issue of the journal Nature. That’s because the birds can’t easily alter their migrations to arrive at breeding grounds when food is most plentiful.

Over the last 20 years, spring temperatures in temperate regions have slowly risen--and many creatures have responded to the shift by breeding earlier. Dutch scientists studied the migratory pied flycatcher, which migrates from Africa to Europe, to see how it was faring.

The bird lays its eggs earlier in spring than it used to, but not early enough to get its share of the food that’s available earlier because of warming. The bird doesn’t migrate any earlier -- possibly because migration timing is biologically “hard-wired.”