Of a Feather: Snow with wings

COURTESY OF ANDY REAGO AND CHRISSY MCCLARREN
It is only natural to begin to reminisce more as one gets older. There is more to look back on. And especially, there are more birds to look back on. Recently, I was asked what my most memorable bird sighting of the year was. For a change, it was an easy thing to name: seeing condors in Colorado. I never expected to see so rare a bird. Never mind 500 miles from where they were “supposed to be.”

Once upon a time migrating geese could be counted on to be flying north in the spring and south in the fall. With the explosion of a resident Canada goose population that is no longer the case. Perhaps because these geese seem to adore landscapes I dislike — golf courses and shopping malls. I don’t really look at them the same way anymore. Of course, it isn’t their fault that they were raised as living decoys for generations and then released without ceremony, their migration impulse destroyed.

Not so the snow goose (Anser caerulescens). During my childhood and adolescence I scanned the rafts of waterfowl on Newburgh Bay in the Hudson River for this species and never saw a single one. They apparently don’t use the Hudson Valley as a flyway, or didn’t in the 1970s. It was not until I moved to central New York in the 1990s that I began to encounter this beautiful bird.

I did not see any snow geese in my youth in part because they were quite rare in the eastern United States at the time. Hunting of this species was banned in the eastern U.S. between 1916 and 1975. Allaboutbirds.org notes that snow goose populations in the central and eastern Arctic have tripled since 1973. Game management strategies in the U.S. and Canada shifted from conservation-based for much of the 20th century to population-control after the 1990s. About 400,000 are killed each year. Unlike the polar bear, snow geese seem to be benefiting from climate change in the polar region, as their population explosion correlates well with increases in temperatures there. It has gotten to a point where the breeding birds are so abundant that they are having a negative impact on the environment in some places.

I began seeing snow geese regularly when I moved to the vicinity of Cayuga Lake, the longest of the 11 Finger Lakes of central New York. These former river valleys were immensely deepened by erosion caused by successive advances of continental ice-sheets. They are oriented roughly north–south on the northern slope of the Allegheny Plateau, the northernmost of a series of physiographic regions on the inboard side of the Appalachians. (Because of Daniel Boone, the Cumberland Plateau is more famous.)

The Finger Lakes are shallow at their north ends and deepen southward; the ice cut downward as it was forced into the narrowing river valleys. There are broad marshes north of the open water of each lake, often drained for agriculture, but preserved at Cayuga Lake as Montezuma Wildlife Refuge. The northern third of Cayuga Lake itself is very shallow and full of aquatic plants rooted on the bottom. (A bass fishing tournament is held there every year.) This is heaven to migrating waterfowl.

New York Route 89 runs along the western shore of the lake, a road I often drove between Ithaca and Rochester. In the fall the lake surface is sometimes like a mirror of the sky and the waterfowl are as visible as objects d’art arranged on a reflective tableau. The gray backs of the diving ducks are readily seen against the dark water, but the snow geese jump out at you like white flowers scattered on colored glass. There were often hundreds of them and sometimes thousands.

As with many widespread species, there are subspecies of geese. In the eastern U.S. we see the greater snow goose, which is about 31 inches long. We also see the common Canada goose, which is about 45 inches long. When they are at rest on the water, snow geese look almost entirely white with only the tips of their black primaries emerging above their tails.

In addition to the greater and lesser populations, there are also color morphs. The darkest version has a white face and white wing coverts and secondaries (which translates into a white bar on their sides when they are at rest). They are also white on the belly and under the tail. The primaries are streaked with white. The birds are otherwise a dark bluish-gray and were once thought to be a separate species called the “blue goose.”

The color is controlled by a single dominant gene. If a blue goose mates with a white goose, all the offspring are dark. But if two blue geese mate, some of the young may be white. The blue phase is much more common in the lesser snow goose of the central and western Arctic.

Their shorter necks and shorter bills give them a more compact appearance compared to Canada geese, from which their color usually distinguishes them anyway. The blue geese are readily distinguished from most diving ducks by their larger size and distribution of white. However, several times on my way up or down Route 89 I spotted white birds out on the lake that turned out to be tundra swans rather than snow geese. The former are much larger birds and entirely white except for their dark bills.

The charm of the snow goose extends to its call. The honking of Canada geese is often described as a wild and thrilling sound. The sound of snow geese is quite different. For one thing it is a distinctly two-noted call and is higher pitched. It can only be described as cheerful.

Bill Chaisson has been a birdwatcher from the age of 10. He is a former managing editor of the Eagle Times and now lives and works in the town of Wilmot. Contact him at [email protected].