Winter Birds of Rocky Mountain National Park

Northern Shrikes are predatory songbirds. Photo: Scott Rashid

by Scott Rashid
Colorado Avian Research and Rehabilitation Institute
Colorado Avian Research and Rehabilitation Institute
​As fall ends and winter begins, birds begin to move to their wintering grounds, or the areas where they will spend the winter months, where they hope food and water is plentiful. Some of the birds that nest here also winter here, but other birds simply arrive in September and October to winter here, here being Colorado and specifically the Estes Valley and Rock Mountain National Park (RMNP).

Migration takes many forms, and in fact, there are multiple types of migrations.  There is elevational migration, latitudinal migration. longitudinal migration, circular migration and leapfrog migration.

Brown-capped Rosy-finch. Photo: Scott Rashid

Different species use these varying types of migration. For example, shorebirds move north through the center of the country, migrate in a more circular form. From their wintering grounds along both coasts, they simply move north through the center of the country as they can feed in the flooded fields during their spring migration. Yet when they migrate in the fall, the center of the country if filled with crops, leading them to migrate south via either east of west coast to winter along the coasts of the Atlantic, Pacific and the Gulf of Mexico, migrating in two large circles.
 
Birds here in the west have an elevational migration. Birds including Clark’s Nutcrackers, Horned Larks, and American Pipits nest either on or close to the Alpine Tundra and winter in Estes Park or along the grasslands of Eastern Colorado. Another example of migration is leapfrog migration. American Crows in the west have this type of movement. For instance, birds here in Estes Park head southeast in the fall/winter and are replaced by northern birds from British Columbia and Alberta, Canada.

The species that both nest here and spend the winter in the Estes Valley include the corvids; Common Ravens, American Crows, Black-billed Magpies, the jays, and the Clark’s nutcrackers. The three species of nuthatches stay here as do some of the Brown Creepers. Townsend’s Solitaires and American Robins remain here as do Chickadees.

Mallards, Common Goldeneye and Common Mergansers remain as do the Canada Geese. Some of the birds of prey winter here as well. These include the Red-tailed Hawks, Bald Eagles, Cooper’s Hawks, Sharp-shinned Hawks, Northern Goshawks, Great Horned Owls, Northern Pygmy-Owls, Boreal Owls, and Northern Saw-whet Owls.

Pine Grosbeaks are common at higher elevations. Photo: Scott Rashid

Birds that migrate out of Estes Park and include, most if not all the warblers, hummingbirds, and flycatchers, Pine Siskins, Hermit and Swainson’s Thrushes, Ruby-crowned Kinglets, Blue-winged Teal and Flammulated Owls.

The birds that will appear in the fall/winter to spend the colder months in Estes Park and other parts of Colorado include the three species of rosy-finches, Evening Grosbeaks, Snow Buntings, Northern Shrikes, Lapland Longspurs, Pine Grosbeaks, Dark-eyed Juncos, and Rough-legged Hawks.

It is a good idea to begin putting out bird seed for the winter birds in mid-October before they begin arriving. Once they are here they will need food to either refuel to continue moving or enough food to keep them here for the winter.

As for what type of seed to put out, sunflower seed is always a good bet, as is millet and suet.  Keep your eyes peeled for any of these species. Look for Black, Gray-crowned and Brown-capped Rosy-finches, Oregon, Slate, and White-winged Juncos, Snow Buntings, Evening Grosbeaks, and White-winged Crossbills.

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