Overwintering Waterfowl

Gadwall (male)

Many species of waterfowl only migrate short distances in the fall and winter – they settle in on lakes and large rivers where the water is still open, and when those start icing over, only fly far enough south until they find the next patch of open water. In Ottawa, parts of the Ottawa and Rideau Rivers remain open year-round, attracting mallards, black ducks, Common Goldeneyes, and a handful of Canada Geese and Common Mergansers. A couple of Barrow’s Goldeneyes show up annually on the Rideau River, and Harlequin Ducks spend their winters on the rapids of the Ottawa River every two or three years. Most other ducks move further south below the snow line, spending the winter on the St. Lawrence River or Lake Ontario. Some, like the Wood Duck, spend their winters in the southern states, while other species, like the Blue-winged Teal, overwinter as far south as the northern coast of South America.

A large number of mallards stay in Ottawa even after their natural food on the shore becomes buried beneath snow and ice because they receive handouts from people – if you go to Mud Lake, you will often see large piles of seed or corn spread out for the birds to feed on. This also happens at Strathcona Park and Billings Bridge. Even storm water ponds that remain partially open due to warmer water temperatures host mallards and American Black Ducks in the winter – the pond on Iber Road in Stittsville is one such place, and the ducks there are also fed by humans. In the winter, the natural food of dabbling ducks includes aquatic insects, seeds and vegetation in shallow water, although I don’t imagine that these food sources are abundant enough in storm water ponds to support the large number of ducks that overwinter there. Diving ducks on the rivers are not dependent on humans, feeding on fish, crustaceans, mollusks, and insect larvae such as dragonfly or mayfly nymphs.

It is always worth checking large flocks of mallards in case another species is present, having realized the advantages of joining the flock: protection in numbers, and a reliable food source. Northern Pintail, Northern Shoveler, Wood Duck and Green-winged Teal are the most common species to overwinter with local mallards, with one or two species present annually, usually at the above-mentioned locations. However, in early January a female Northern Pintail showed up at a relatively new storm water pond at Half Moon Bay Park in Barrhaven, along with an American Coot. Pintails are common enough that I usually see a few during migration, but American Coots can be more difficult to find so I felt it was worth a trip.

Northern Pintail (female)

Female pintails look similar to female mallards and can be hard to pick out among a large group of ducks. There were around 150 mallards present, but no American Black Ducks which seemed a bit odd. The female pintail has a gray bill, plain brown head, and a more elaborate pattern on the feathers of her body. She is also slightly smaller than a mallard. Eventually I found her resting on the rocks at the edge of the pond, closing her eyes for a brief mid-day snooze. Northern Pintails normally overwinter in the U.S., Mexico and Caribbean, though there are many eBird reports of them in the winter months in southern Ontario from ponds and along the shores of Lakes Erie and Ontario.

Northern Pintail (female)

The American Coot was further out, diving in the water close to the veneer of ice that covered the rest of the pond. Although it floats like a duck and swims like a duck, it is a member of Family Rallidae, a bird family that includes the rails, coots, crakes, and gallinules. Genetically it is more similar to the elusive marsh rails, gallinules, moorhens, and the much larger Sandhill Crane than it is to the mallards, pintails and other dabbling ducks! One clue to its identity is in the feet: instead of webbed feet, it has disproportionately long toes that recall its dinosaur ancestry. The toes have lobes of skin attached that help propel it through the water then fold back to allow it to easily walk on land.

American Coot

Ontario and western Quebec form the eastern-most part of its breeding range; they are much more numerous out west, where they are found year-round in southern B.C., along the western states and east through Louisiana. I saw plenty of coots at Sunset Park and the Henderson Bird Viewing Preserve in Las Vegas on both of my trips there, with overwintering birds numbering in the hundreds at both locations. They do not typically overwinter in Ottawa, and can be scarce during migration, so it was not a difficult decision to venture out to Barrhaven and see this uncommon species.

On January 18th another rare overwintering duck was found in Ottawa – this one a male Gadwall at the Iber Road storm water pond in Stittsville. There is usually open water here in the winter, which usually hosts a couple hundred mallards and sometimes several American Black Ducks and Canada Geese. As a storm water pond, it is terrific for overwintering waterfowl, but as a birding spot it leaves much to be desired as there is no real habitat surrounding the pond – it has a small open grassy area with a few trees on the north and east sides, with commercial buildings forming the northern and southern boundaries. Iber Road forms its eastern boundary, while the backyards of houses in the subdivision to the west provide lots of trees for songbirds passing through. A small path behind the pond provides access between the subdivision and Iber Road, and it is here where I’ve seen people putting out feed for the ducks.

Gadwall (male)

There were, by my estimate, about 1,000 ducks in the pond when I visited on January 24th. More than half were on the ice, while the rest were swimming in the pond. I had no idea how I was going to find the Gadwall, but when I started scanning the ducks in the pond it didn’t take that long to find him. He was dark-billed and had a darker body than the mallards, and as he was swimming by himself he wasn’t too difficult to find. I stayed long enough to give the rest of the ducks a thorough scan – I counted 57 American Black Ducks and three Mallard x Black Duck hybrids, but no other unusual species were present.

Gadwall do not migrate very far – while most of these ducks spend the winter in the United States, many others overwinter in southern Ontario below the snow line. Lake Ontario is a good place to see them, as they were a fairly common sight at the ferry dock at Amherst Island in years when the water was open, but Lake Erie, Lake St. Clair, and the Detroit River are also good places to see them.

Gadwall (male)

The Gadwall brought my year list up to 43 species, far ahead of where I was last year. I’m still missing a lot of common winter species, such as Merlin, Cooper’s Hawk, Northern Shrike (sadly not as common as they used to be), Bald Eagle, Barred Owl, Horned Lark, and Barrow’s Goldeneye, but those should come with time. Although surprise birds are my favourite way of finding birds, it’s always great to have a target, too, as it provides the motivation to check out new places and spots I rarely visit.

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