Tundra swans in flight. Courtesy USGS.

It’s a long airplane flight from Baltimore to northern Alaska. But what if you were a tundra swan? This time of year, these birds head off from their wintering grounds in the Chesapeake Bay, flying about 4,000 miles to their breeding grounds in the Arctic National Wildlife Refuge and other spots across Alaska’s Arctic coastline. Typically, they fly through Pennsylvania, Ohio, Michigan, Wisconsin, Minnesota, and North Dakota, stopping at national wildlife refuges and other suitable spots. Read more