Birds that normally eat insects switch to antioxidant-rich berries just before starting their long journey south for winter.
- Insect-eating songbirds switch to fruits rich in antioxidants before migrating.
- The antioxidants apparently help the birds deal with the stress of migration.
- Birds and other wildlife could help biochemists prospect for useful substances in nature.
Bug-chomping songbirds have been discovered doing something remarkable before migrating south for the winter: They switch, awkwardly, to berries rich in antioxidants.
The dietary change has less to do with fattening up and more to do with stocking up on nutrients to help their bodies deal with the stresses of migration, say researchers.
"It has been known for some time, this phenomenon of birds switching to fruits in the fall," said bird researcher Scott McWilliams of the University of Rhode Island. It was assumed that the birds were packing in extra fats or carbs during cooler weeks when insects were on the wane. "But that didn't explain it enough."