DELMARVA ALMANAC

The Snow Goose Spectacle

by Jim Rapp

If there's one wildlife experience that defines Delmarva in the winter, it may be the annual arrival of migrating Snow Geese to our coastal marshes and farm fields.

This is truly one of the greatest animal migrations on the planet, and the spectacle is best witnessed in and around Bombay Hook National Wildlife Refuge northeast of Dover, Delaware.

In late November, hundreds of thousands of Snow Geese migrate to the Peninsula from summer breeding grounds in the Arctic Tundra. If you're in the right spot to witness their arrival, you may think there is an ominous snow shower looming in the distance. As they approach, geese migrating in crisp V-shapes morph into snaking, shifting U-formations as they prepare for landing. Massive flocks can temporarily block out the sun.

As they get closer, thousands of geese create a cresting wave of squawks and honks. The noise builds until you can't hear anything else around you. The deafening chorus can create a ringing in your ears that will take you hours to shake loose.

They float to the ground from higher altitudes in layer after layer of white, tumbling geese. As they make landfall, they begin to cover the ground, first in just a few patches here and there, but before you know it, the field or marsh is blanketed in a flock of mostly white snow geese.

If you peer through your binoculars or spotting scope, you will mostly see chunky, white birds with black wingtips, a pink cone-shaped bill with a dark line along it, often called a "grinning patch," and reddish-pink feet and legs. There is also a "blue" phase, where the body of the snow goose is bluish-gray.

This blue color morph is controlled by a single gene, with blue being partially dominant over white. If a blue snow goose mates with a white snow goose, their babies will be blue. If two white geese mate, they have only white offspring. If two blue geese mate, they will have mostly blue babies, with a few white ones, too.

If you scan Snow Goose flocks carefully, you may also find another similar-looking species. The dainty Ross's Goose looks like a mini-Snow Goose. The Ross's Goose has a petite round head and a stout, short beak that lacks the dark "grinning patch" that looks like black lips on a Snow Goose.

Tundra Swans also migrate to Delmarva in the winter, and can be found feeding in marshes and fields. Tundra Swans are much larger than Snow Geese, with longer necks, and wings without black wingtips. Tundra Swans also have dark bills and feet, unlike the pink bill and feet of the Snow Goose.

The snow goose spectacle can be witnessed up and down the Delmarva coast, but your best chance for this experience is at Bombay Hook National Wildlife Refuge. Every winter, Bombay Hook hosts as many as 200,000 snow geese.

The name Bombay Hook is a throwback to Delaware's Dutch settlement era. Bombay Hook is derived from the Dutch words for "Little-Tree Point." The National Wildlife Refuge was established in 1937, 21 years after snow goose hunting was banned in the U.S. due to unregulated harvesting. Bombay Hook serves as a link in the chain of wildlife refuges extending from Canada to the Gulf of Mexico, and is a critical feeding stop for birds that migrate along the Atlantic Flyway.

The refuge is mostly marsh, but also includes freshwater impoundments and forests that are managed for wildlife. You can tour the 12 mile wildlife drive by car, and stop along the way to explore nature trails and observation towers overlooking the four fresh water impoundment, known as Raymond Pool, Shearness Pool, Bear Swamp Pool, and Finis Pool. Water levels in the impoundments are flooded in the fall to give ducks, geese and swans access to plant seeds that germinated over the summer. The pools are lowered in the spring to provide mudflats for migrating shorebirds.

Thanks in large part to the network of national wildlife refuges, the 1916 ban on snow goose hunting was lifted in 1975 after populations had recovered. Since then, their populations have continued to grow to the point that, today, snow geese are one of the most abundant waterfowl species on the planet.

Due to the sheer number of wintering birds and their voracious appetites, some areas at Bombay Hook suffer from too many snow geese overgrazing in the open marsh areas. Hunting is allowed during the Delaware season for snow geese when permitted by the Refuge Manager.

When feeding in a coastal marsh, Snow Geese use their strong, serrated bills to rip grasses from the mud, which can have devastating ecological implications. A healthy salt marsh can become a barren mud flat if there are too many hungry snow geese.

Ever heard the saying "faster than poop through a goose?" Anyone who has studied snow goose feeding habits closely will verify the authenticity of this phrase. Food passes through the goose's gut in just an hour or two, producing up to 15 droppings per hour. The rate is highest when a goose is gobbling up the roots of marsh plants, due to the high fiber content and incidental swallowing of mud.

Snow geese are also found feeding in Bombay Hook's nearby farm fields on grasses, clover and leftover corn and soybeans. In feeding flocks, lookouts keep an eye out for eagles and other predators. If they see a threat, the lookout will call out to the rest of the flock, which then takes flight.

As impressive as witnessing the arrival of thousands of snow geese, watching them explode in unison into a liftoff flight is equally thrilling. Seemingly without warning, the feeding flock will burst into the air, with the sound of beating wings and squawking beaks merging into one deafening wall of sound. The experience can take your breath away.

One of the best times to experience snow goose flights at Bombay Hook is just before the sun goes down. During the middle of the day, the birds tend to feed on the nearby farm fields, but they return to the refuge to spend the night. If you time your trip well, you may get lucky with the magical combination of a cacophonous snow goose flight against the backdrop of a stunning sunset. Follow that with drinks and dinner at one of Dover's excellent restaurants, and you have the ending to a perfect winter day on Delmarva.

If you want to experience Delmarva's snow goose spectacle and enjoy winter wildlife watching with expert guides, check out the new Delmarva Winter Birding Weekend, which will be held January 29 through 31. For more information, please visit DelmarvaBirding.com.

References:


http://www.fws.gov/refuge/bombay_hook/