DNA Clues to Monarch Migration

Fall bird migration is now accelerating dramatically over Michigan. About 37 million birds had already migrated out of the state during the first week of September, with millions more moving south on recent nights. Most songbird migration occurs after dark, so an apparently quiet Sunday night can have an enormous invisible procession passing overhead. Audubon's Great Lakes work notes that hummingbirds, songbirds, shorebirds, waterfowl and raptors are making journeys that can ultimately reach Mexico, Central America, the Caribbean and South America.