In addition to the Year-round Birds, there are some species (the Winter Visitors) that are only seen here during the winter months. These together make up the normal list of species that one can expect to see in Calgary during the winter months.
In addition, some individual birds from species that are not normally here in the winter sometimes try to overwinter here.
Gus Yaki has written the following informative article on some winter birds that are worth looking for.
Some of the birds that are present within the city in the first quarter, January-March, are ones that normally shouldn’t be here at all, at this time of the year. Most disappear after the first major cold spell. This could include one or more warbler species that normally don’t reappear again until May in the second quarter, if at all.
If a Snowy Owl (or any owl other than a Great Horned) is reported, try to see it immediately. In the arctic, Snowy Owls are most dependent upon lemmings, whose populations collapse, on average, every four years. Lemming numbers did collapse in 2009; so many Snowy Owls came south. However, there is always a high mortality when they do this. The remaining owls went back to the tundra, but because the lemming numbers were still low, the surviving owls, which have returned this year in the ”Shadow Flight”, are now further reduced in numbers.
Some of the other possible species that may not stay around and may not be seen again until the second or later quarters, should be pursued as soon as possible. This includes Greater White-fronted Goose, Snow Goose, Redhead, Ring-necked Duck, Greater Scaup and Red-breasted Merganser. If any loon is sighted, try to see it right away too, before it moves on. If a Gyrfalcon, Peregrine Falcon or Prairie Falcon is reported in the city, again spy it as soon as possible. Most gulls have left by January, but a Glaucous Gull may visit us. Again, it would be wise to search for it – as none may turn up again during the rest of the year.
American Three-toed and Black-backed Woodpecker appear in Calgary in some winters. If one is reported, get out to see it while it is here. Gray Jays used to be regular winter residents, but in recent years are seldom seen, perhaps due to global warming. If one is reported, perhaps at Shannon Terrace in Fish Creek Prov. Park, it would be worthwhile trying to see it. Similarly, Boreal Chickadees, also in the Shannon Terrace area, are becoming scarce and are worth pursuing. Another bird worth looking for is the American Dipper, from the fast-flowing streams in the mountains. When those waters freeze, some dippers move down to our elevation. Snow Buntings and Horned Larks are also worth looking for in the city, when reported. Evening Grosbeaks have become very scarce, but were reported several times in 2009. If they are again sighted, try to find them before they move on, too.
Gus Yaki, 403-243-2248