Spring Migration of Birds in the Northwoods

Spring migration brings millions of birds through the Northwoods. These movements along the Mississippi Flyway signal that winter is over. While the calendar or the thermometer may suggest otherwise, these arrivals serve as a biological confirmation that the season has changed.

This cycle relies on a healthy environment. The 1,500 lakes and vast forests of the Northwoods provide the essential fuel for the journey.

Tracking the Arrival

Observers can track the progress of the season through three specific waves of activity:

• The Ice Breakers (Late February to March): Common Mergansers appear first. They follow open water leads on the Wisconsin River or local creeks while the lakes remain frozen. By mid-March, the rattling calls of Sandhill Cranes return to thawing marshes.

• The Waterfowl Push (Mid-April): This stage depends on ice-out. Large groups of ducks and geese rest on lakes like Minocqua and Tomahawk as soon as the ice retreats.

• The Warbler Wave (May): This is the peak of the season. Colorful neotropical migrants like Baltimore Orioles and Rose-breasted Grosbeaks arrive from Central and South America. Ruby-throated Hummingbirds typically return by Mother’s Day.

Where to Find the Migration

Specific habitats act as stopover points where birds congregate to rest and feed: