Annual snow geese migration thrills some, frustrates others
You’re driving down the road on a brisk fall day, and then all of a sudden you see it — a field of white. As you slow down to take a closer look, the field explodes into the sky, a blizzard of beating wings and a symphony of squawking.
The snow geese are back.
These migrating waterfowl, whose scientific name is Anser caerulescens, breed in scattered areas across the Arctic from eastern Canada to Alaska and in marshes around Hudson Bay. They make their yearly pilgrimage to warmer climes as the days grow shorter, leaving the northern tundra and traveling along the so-called Atlantic Flyway to settle in areas with open agricultural fields and coastal marshes. The snow geese that winter in Delaware largely come from the eastern Canadian Arctic and a small area of western Greenland, according to Chris Bennett, vice president and program chairman of the Delmarva Ornithological Society.
“One of the ways that we know where the local geese are from is that some of them have yellow collars,” Bennett explains. “Birders report the geese to the Bird Banding Laboratory in Maryland, and all of those with collars come from Bylot Island in Canada.” The banding laboratory, established in 1920, is part of the Patuxent Wildlife Research Center.
According to the National Audubon Society, snow geese fall into two categories — the lesser snow goose and the greater snow goose, both of which have white and blue phases (though adult greater snow geese are primarily white). As the name indicates, lesser snow geese are smaller than their cousins. These birds may mate for life, usually first breeding at age 3. Pairs typically have three to five eggs, with an incubation period of about 22 days. The young usually leave the nest within a few hours of hatching, finding their own food but still tended to by both parents. The young fledge at 42 to 50 days. A full-grown goose weighs between 3½ and just over 7 pounds and has a wingspan of about 4½ feet.
In the 1970s and 1980s, snow geese from northeastern Canada primarily wintered in North and South Carolina, but over the years their winter resting grounds have moved north, the result of generally milder weather and less snow cover, explains Bennett. The waterfowl, which eat grasses and grains, feed in fields of corn, soybeans or winter wheat during the day and roost at night at Prime Hook National Wildlife Refuge, Bombay Hook National Wildlife Refuge or other marshy areas along Delaware Bay. They typically begin arriving in October or November and leave in March, although in warmer years they may arrive later.
“I have been watching birds for over 40 years, and I have come to realize that you have to expect change,” notes Jeff Gordon, president of the American Birding Association, based in Delaware City. “The geese move around depending on changes in the weather and sea levels, which have a big impact on the salt marshes. It’s hard to predict how climate change will affect the annual migration.”
While the snow geese population dropped in the early 1900s, it began to rebound after a hunting ban was imposed in 1916. Though the ban was lifted in 1975, today snow geese are one of the most plentiful waterfowl species in the world, with an estimated breeding population of more than 5 million, an increase of 300 percent since the mid-1970s. The population that travels along the Atlantic Flyway is estimated at about 800,000.
According to the annual Aerial Waterfowl Survey, which has been conducted since the 1970s by the Delaware Department of Natural Resources and Environmental Control’s Division of Fish & Wildlife, the number of snow geese that make our state their winter home fluctuates from less than 200,000 to almost 1 million. The highest number recorded was just over 929,000 in 1997, while in 2017 that number dropped to about 197,000, down from the more recent high of nearly 570,000 in 2014.
“It depends a lot on weather,” says Justyn Foth, a waterfowl biologist with DNREC. “Waterfowl are kind of lazy when they migrate, they’re only going to go as far south as they absolutely have to, and that’s usually right at the winter snow line. Last year, we were the winter snow line, and we had an abundance of waterfowl initially, but then we had three northeasters hit in January and February and the geese moved even further south.”
Although local photographers and birders welcome the return of snow geese each fall, farmers tend to be less than thrilled. Unlike Canada geese, which eat only the tops of vegetation, snow geese have strong, serrated bills that they use to rip grasses up by their roots, effectively destroying the plant. Farmers employ various methods to deter the birds from eating their crops, from placing large bald eagle cutouts in fields to chasing them off with dogs and all-terrain vehicles to shooting guns in the air. Some methods are more successful than others.
“Near the Air Force base in Dover, there’s a big field with winter wheat where the farmer has parked an old pickup truck in the middle of the field,” notes Bennett. “Before that, the field was covered in snow geese, but the pickup truck seems to have done the job.”
However, farmers who lease their land to hunters welcome the migration each year. In Delaware, snow geese hunting extends from early October to early February, with a daily bag limit of 25. In recent years, DNREC has extended the hunting season to April 12 through a special Snow Goose Conservation Order, which it uses to reduce and stabilize the population. The conservation order applies only to snow geese and goes into effect after Delaware’s regular waterfowl hunting season closes. During the order period, snow geese can be hunted every day except Sunday, with no daily bag and possession limits.
“Our goal is to get the Atlantic Flyway population down to 600,000,” explains Foth. “Most of the birds harvested during hunting season are juveniles, so the thought is if you remove the juveniles from the breeding population for a number of years, once the adults phase out of the population, you’ll have a much smaller population. Snow geese can live 20 or 30 years, so the [goals of the] conservation order in place now won’t be realized for another decade or so.”
Whether you love them or hate them, the annual migration of snow geese can be an amazing spectacle to witness, with thousands of birds converging on a field like a blanket of snow and then taking flight in an instant, their calls reverberating in your ears.
“It’s wonderful to see and hear,” says Gordon. “Around the world, flocks of waterfowl are something that people just really enjoy and have sometimes taken as a symbol of the goodwill of God. Migrations alert us to the passage of time and the annual cycle of renewal. That’s a big part of what it means to be human, to have this awareness of the other life around us.”
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