Ross’s Goose - a rare visitor to Maryland

Diminutive Ross's goose connects a country
On the Wing / By Michael Burke - Bay Journal

A thousand Canada geese blanket the small pond and adjacent land. They are feeding, resting and making a continuous low racket with their irregular honking and wing flapping.

In other words, everything is perfectly normal for a winter’s day in Chesapeake country. Except, that is, for that small white goose sticking out like a brilliant pearl against a background of browns and blacks. My first thought is that it’s a snow goose; but it’s obviously too small. Besides its bill is, well, stubby.

I quickly consulted my pocket field guide, but I can’t find this bird.

Like many birders, I have a hefty “The Sibley Guide to Birds” in my car. I took careful note of his field marks, a task made easy by the goose’s slow grazing in the bright sunshine. After I’ve had my viewing fill, I head back to the car and the big field guide. And there it is on page 78: a Ross’s goose (Chen rossii). It’s my first encounter with a Ross’s—a rare visitor to Maryland.

The Ross’s goose looks remarkably like the snow goose. Like their cousins, they’re all white except for jet black wing tips. But the Ross’s wingspan is just 45 inches, compared with the snow goose’s 55 inches. What’s more, Ross’s goose weighs half as much, coming in at just less than 3 pounds.

And then there’s that bill. Snow geese and Canada geese have substantial bills. But this little Ross’s goose seems less formidable than his cousins, and I think that small bill is a big reason.

In the field, the overall size of a bird can be deceptive because of distance and lighting. There’s no mistaking the Ross’s stubby pink bill, however, for the more imposing variety worn by a snow goose.

Ross’s geese breed high in the Arctic tundra. Some nest on the western shore of Hudson Bay, but most nest even farther north in the Queen Maud Gulf Migratory Bird Sanctuary in Nunavut, Canada.

The much more common snow goose’s breeding range encompasses these areas and much more.

There is evidence that Ross’s and snow geese will sometimes interbreed. The Ross’s, like the snow, has a dark morph, but it is quite rare and Sibley speculates that the dark-feathered Ross’s may really be hybrids.

It takes three weeks for eggs to incubate in this northern nesting range. And it will take the young a month and a half before they are ready to fledge. The Ross’s goose feeds primarily on plant materials and aquatic invertebrates throughout their lifetimes.

When these geese head south for the winter they replicate their breeding geography. The Ross’s has just a few locations it frequents, while the more prevalent snow goose encompasses all those areas and quite a few more.

Ross’s usually winters in central California in the Sacramento Valley. A few go to New Mexico and others to the Texas Gulf Coast. Snow geese migrate to the same areas, although they form separate flocks on the winter range. Snow geese also winter on the East Coast, of course, including the Chesapeake. And this winter, so has a Ross’s.

A check of local Christmas bird count data reveals just how rare my sighting was. During many years, Maryland counts have only come up with a single individual. Some years show none.

As I take a second look at the Ross’s goose, my mind glides back to a pair of work trips I took to Sacramento last year.

The first was to discuss the differences and similarities between the Chesapeake Bay Program’s management efforts and those being utilized by its sister program known as CALFED. The second was a science conference in which the relatively young California effort was looking to the Chesapeake for comparative uses of environmental indicators.

But when I stood there on a Chesapeake tributary in the middle of winter, I realized that the most important connection is right in front of me. A Ross’s goose that typically winters in the Sacramento Valley is here this year. In either location it will need clean water, ample habitat and a steady supply of food.

It is the living resources that stretch across the continent that bind us. And it’s all carried off with elegant grace by this diminutive goose.

Mike Burke is an amateur naturalist who lives in Cheverly, MD.

Diminutive Ross's goose connects a country
Article from Bay Journal - Feb 2007

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