Diving Ducks arriving on Lake Ontario

Nature Notes for October 25, 2013

People are always surprised to learn that birders go into the field throughout the year, including the depths of winter. Although the southern Ontario Hawk Watches will be operating for only a few more weeks and migration of small land birds has slowed to a trickle, there are still birds to be seen.

For Northumberland birders, the focus tends to drift toward Lake Ontario to search for waterfowl. For many diving ducks, Lake Ontario is south.

This is the time of year when huge flocks of Red-breasted Mergansers can sometimes be seen. These ducks breed near large bodies of water throughout the boreal forest. Although some winter on the Great Lakes, most of the ones seen locally are en route to wintering grounds along the Atlantic coast and the Gulf of Mexico.

LesserScaup frequently appear in large “rafts” of birds. These ducks nest throughout the north and west of the continent and are migrating through to wintering grounds in the southern U.S.- Although a few may persist throughout the winter, the majority of the wintering scaup are Greater Scaup.

Greater Scaup look very similar to Lesser Scaup. The males of both species have dark heads and breasts, white sides and black tail. Lessers have a purplish sheen to the head and Greaters are green, but observers are not often close enough to the birds, or in good enough light conditions, to see this difference. The females of both are brown with a white patch at the base of the bill. The white patch is bigger in the Greater Scaup, but again this if often difficult to see. It is easiest to tell these two species apart in flight by the extent of white at the base of flight feathers. This is, of course, a marking that is impossible to see on a sleeping bird in windy conditions. Frequently, I just identify them as “scaup” without trying to differentiate the two species.

A few Black Scoters have been spotted in recent days. These ducks breed in the northern Quebec and Labrador. Some also breed in Nunavut and central Alaska.  The ones seen on Lake Ontario are passing through to wintering areas on the Atlantic coast.

Long-tailedDucks breed throughout the Arctic as far north as Ellesmere Island. In winter on Lake Ontario, we see them in a plumage which is primarily black and white. In the breeding season, they are mostly brown. The male has long tail feathers, which gives this species its name.

I haven’t yet seen any Common Goldeneye or Bufflehead, two other common wintering ducks on Lake Ontario. Like many other wintering ducks, they are primarily black and white. These two species breed primarily in the boreal forest, where they nest in tree cavities. Numbers of these two ducks will arrive on Lake Ontario in the next few weeks to spend the winter here.

Along with these more common species, a single female plumaged Harlequin Duck was spotted off Lake St., Port Hope on October 14. This species favours forested mountain streams in the summer. The eastern population breeds in Labrador, the Ungava Peninsula of Quebec and southern Greenland. When it comes to the Great Lakes, it can often be found quite close to shore, foraging for mollusks amongst the rocks of habour jetties.

Probably by the time this column appears in print, many of the ducks mentioned will have arrived on Northumberland’s section of Lake Ontario. Perhaps readers will have the opportunity to look for them.