The Great Migration

About 45,000 tundra swans, snow geese, and dozens of other bird species travel from Alaska and parts of Canada to spend the winter on North Carolina’s coast. This great migration gives scientists an opportunity to monitor the health of the population and how it is adapting to environmental changes.

POCOSIN LAKES NATIONAL WILDLIFE REFUGE — If you stand in the middle of a field on the Pocosin Lakes National Wildlife Refuge anytime during the day between October and February, you won’t be able to hear yourself think.

That’s because you are bombarded from all sides by honking, quacking, squawking, chattering birds... Migratory waterfowl. More than 100,000 of the winged creatures in all shapes and sizes are flying, taking off, landing, floating, swimming, and walking through fields. The sights and sounds are amazing, deafening, and inescapable because you will find some type of bird everywhere you look.

Call it Mother Nature’s feathered surround-sound.

“I never get tired of it because it’s just different than what you see at most places,” says Howard Phillips, manager of the Pocosin Lakes National Wildlife Refuge. “Yes it is noisy but it is also beautiful and it’s part of the creation that we are supposed to take care of and that’s what we are doing.”

The birds spend the winter in the eastern part of North Carolina because the Pocosin Lakes Wildlife Refuge, near Columbia, lies in the middle of the Atlantic Flyway.

The flyway is a migration path that generally follows the Atlantic coast of the United States and the Appalachian Mountains. The end points are in Canada's Maritime provinces to the north and the Gulf of Mexico to the south. It’s one of four waterfowl flyways that stretch across the country.

If you stand on the shore of Pungo Lake with biologist Elaine Barr, you’ll get an idea of just how many types of birds spend the winter in North Carolina. The 3800-acre lake is the focal point of the refuge.

“I see the tundra swans because they are the largest birds,” says Barr, as she scans the lake with binoculars. “There are coots swimming around and just beyond the swans are a couple thousand Green Winged Teal, which are some of the smallest ducks. I also see some Gadwell, some black ducks, and a Northern Pintail now.”

Barr performs ground and aerial surveys to count the birds. I asked her if she does her counting the usual way, one number at a time.  

“That would be a challenge,” Barr answers, laughing. “It’s very visual and it takes a lot of practice, but you train your eye to say that’s 10, 50, 100, 500, 1000, 5000 birds at a time. It’s not perfect, but it’s a pretty accurate way to do it. It’s really about training your eye to see those patterns.”

There's a thin white line on the far side of the lake. It looks like snow, even though it wasn’t cold enough for that. Then, the line starts moving, and flying, and suddenly the far said of lake is almost invisible because it's blocked by a white cloud that moved, and pulsed, and turned to grey and then to white.

“Those are the snow geese,” explained Barr. “They spend their time here at the lake and then in the fields. You’re looking at about 40,000 snow geese right now.”

Unfortunately the birds didn’t fly towards us. After a few minutes they settled back down on the lake. It was a spectacular sight nonetheless.

The surveys of migratory waterfowl provide scientists with a way to monitor the health of large populations at the present time and over time. There are bird counts that date back to the 1960s, which provides researchers with a way to see population trends over time. The results of bird counts are sent to researchers across the United States and in Canada.

The refuge is scientifically managed to provide the best habitat for migrating waterfowl. The birds spend their time on the water and in the fields, resting from the journey south, and preparing for their return north.

In addition to the lake, the refuge runs a cooperative farming program. Refuge managers bring in local farmers to grow the crops. But instead of paying the refuge rent, the farmers are asked to leave some of the crop in the ground for waterfowl.

The refuge also operates what are called moist soil units. The units are acres of land in which the water levels can be manipulated using a series of pumps and drainage ditches. The areas are flooded to allow high quality, natural or native plants that are high in food value for waterfowl to grow in the spring and summer. As migration season approaches, the land is drained and the plants are ready to eat when the birds arrive.

“Because wetlands are so scarce, you have to find new and improved ways of managing for migrating waterfowl because more and more birds are using the same amount of land,” adds Phillips. “But I think we are seeing conditions improve with the conservation efforts that are going on here and at refuges nationwide.”

Researchers say while their counts of specific bird species may rise and fall somewhat from year to year, the overall counts of migrating waterfowl are holding steady. The refuge managers say the bird counts are good news and a sign the work of the refuge is succeeding.


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