World Migratory Bird Day
Birds Connect Our World
World Migratory Bird Day is celebrated on the second Saturday of May in Canada and the United States, a time to recognize one of nature’s greatest phenomena — the seasonal movements of birds across the globe. But we can celebrate birds — migratory and otherwise — every day.
What Migration Means
Migration is a seasonal, large-scale movement of animals (in this case, birds) between breeding and nonbreeding areas. Birds migrate to make use of resources that are plentiful in one region at certain times but scarce at others.
Not all birds migrate. Many are resident (nonmigratory), remaining in the same area year-round, while others make only local or short-distance movements rather than long-distance north–south migrations. Some species travel a few hundred miles, while others undertake epic journeys across oceans or between hemispheres.
Migration is risky. Birds face predation, storms, energy depletion, and hazards from human structures such as wind turbines, buildings, and power lines. Many birds depend on stopover sites — safe places to rest and refuel along the way. In addition to their resident habitates, if these key stopover sites are degraded or lost, the birds may not survive the trip.
Birds’ navigation is remarkable. Birds use cues such as the position of the sun and stars, the Earth’s magnetic field, visual landmarks, and even smells to find their way across thousands of miles — and many return to the very same nesting tree or shoreline each year.
Our Great Blue Herons, Here and Away
Our local great blue herons illustrate how migration works. In colder parts of North America, herons fly south in the fall to find open water and abundant feeding grounds, returning in spring to their breeding colonies. In warmer areas, some birds remain through the year.
When herons leave their collective nesting site (rookery) at the end of summer, it’s part of this natural rhythm. But if they leave during nesting season, it’s a sign of disturbance, not migration — often caused by nearby tree cutting, noise, or other human activity. Protecting heron colonies helps ensure their return each spring, and the survival of our local populations.
The Mystery of Where Birds Go
For much of history, humans didn’t know where birds went in winter. Some early naturalists even believed that swallows sank underwater or buried themselves in mud until spring. The truth began to emerge in the early 1800s when a stork was found in Germany with an African spear embedded in its neck — proof that birds travel long distances between continents. From that moment, migration became a subject of scientific discovery and wonder.
What We Can Do to Protect Migratory Birds
Even small actions make a difference for migratory birds:
Turn off nonessential lights at night in spring and fall. Most birds migrate after dark, and artificial lights can confuse them.
Protect heron rookeries and other nesting sites during breeding season (April–August) by avoiding disturbance or tree removal nearby.
Make windows safer with decals or screens to reduce collisions.
Preserve wetlands and natural shorelines, which provide feeding and resting places during migration.
Learn and share — understanding migration helps us recognize how fragile and interconnected these journeys are.
Beyond individual actions, we also need collective efforts to protect and restore habitat — the wetlands, forests, and waterways that migratory birds depend on throughout their journeys.
Each spring, birds complete their ancient circuits across the sky. Protecting their routes and habitats ensures that this great movement — the one that truly connects our world — continues for generations to come.
Sandhill crane migration, Platte River, Nebraska (photo: Lynn Cornell)