Snow geese are fascinating to watch. What appears to be a giant carpet of lazy white fluff balls bobbing in the water or nibbling leftover grain in a field will often take off all at once. Loudly swirling overhead with no apparent
destination, they suddenly land right where they were. They are easily spooked by an eagle soaring or a fox prowling nearby.
As snow geese fans savor the scene, farmers and wildlife biologists watch the annual arrival with concern. Sometimes, there can be too much of a good thing.
“Snow geese have insatiable appetites,” said Ronald Ketter, who volunteers with waterfowl surveys at Blackwater National Wildlife Refuge in Cambridge, Maryland. “Unlike Canada Geese, which tend to clip off vegetation leaving roots intact, snow geese often rip out plants by the root.”
In large numbers, snow geese can have a significant negative impact on wetland and farm vegetation. From early winter through March, these beautiful, feathered herbivores (plant eaters) devour fall’s leftover corn and wheat and gobble up new stems of winter plantings. They often leave behind muddy bare patches of ground.
The population of snow geese throughout North America has risen from less than 1 million in 1970, according to several estimates, to at least 13 million, the U.S. Fish and Wildlife Service says.
“The typical flock size at Blackwater is around 2,000 snow geese, but as many as 11,000 have been present,” he said.
After a mild start to the season this year, snow geese began showing up at the refuge January 6.
Bombay Hook National Wildlife Refuge in Smyrna, Delaware — one of the first stops on the migration route — has had 200,000 snow geese visit before they spread out for other areas.
“Cold weather and accompanying ice and snow to our north will typically push birds south as they search for food and open water,” said Paul Peditto, Maryland’s Wildlife and Heritage Service director. “The more severe that cold weather is, the more dramatic migrations to more southerly locations can be.”
And, after finding new food sources, the snow geese return well-fed to the Arctic, where their huge numbers have stripped much of the plant life from their nesting sites.
“Any population can reach a point where it is overabundant, stressing its own resources as well as those of other animals,” said Josh Homyack, a wildlife biologist with Maryland’s Department of Natural Resources.
U.S. and Canadian wildlife biologists are working together to balance the welfare of these birds, the habitat and environmental concerns they pose, and the role of hunters in keeping snow geese populations in check. They’re finding that it’s an ongoing, complicated task.
But that humongous wave of soaring snow geese is marvelous to see.
Hear snow geese sounds — allaboutbirds.org/guide/Snow_Goose/overview.
Watch a huge flock of spooked snow geese swirling over a pond at Blackwater National Wildlife Refuge: youtu.be/If2vRTW1XCM.
If you go
Weather-dependent sightings — the colder the better — are best in early mornings and late afternoons at the refuges. (During the government shutdown, the drives through the two wildlife refuges listed below are open, but visitor centers and support services are closed.)
Blackwater National Wildlife Refuge: 2145 Key Wallace Drive, Cambridge, Maryland. Call 410-228-2677 or visit fws.gov/refuge/Blackwater.
Bombay Hook National Wildlife Refuge: 2591 Whitehall Neck Road, Smyrna, Delaware. Call 302-653-9345 or visit fws.gov/refuge/Bombay_Hook.
Color variations can be found in huge flocks of snow geese.
Adult white-phase snow geese have white bodies and black wing tips. Blue-phase adults (also called dark morph or blue goose) have dark bodies and white heads. Juveniles of each vary from cream to grayish in color. Their heads are often stained a dull rust color because of iron in the soil where these geese forage.