Originally printed in the Dec. 4, 2002 edition of the Illinois Valley News
The Illinois Valley has been invaded again. Instead of firefighters or travel trailers, we have been invaded by birds from the north. We are not on a major flyway for waterfowl but we do have some songbirds that are commonly found somewhere else during the summer and are now here. The Oregon junco, a little gray sparrow-like bird with a black head, is a vertical migrant. They are found at the Oregon Caves or higher during the summer, and moves down into the valley areas for food and winter protection.
The American robin is a north-south migratory bird. The Illinois Valley is in an overlap region between two races of robins. The robins we saw in the summer have moved to Southern California, Mexico or Central America. The robins we see now were in Alaska, Canada and Washington during the summer. The two types are not very distinct and because of interbreeding the populations are very similar.
In the northern race, which we have during the winter, the male is darker in the head area with the back of the neck and upper back being almost black. The southern race has a black area on the head but not as extended. The northern males have darker red breast feathers and less white in the chin, right under the beak. Also by looking closely one can usually see white corners on the outside tail feathers which is not visible on the southern forms. The female of both races is about the same, which is lighter and less noticeable than the male.
Both groups of robins have the same basic diet, which is not worms in the summer, as it is in the winter. In the summer, insects and berries are more available and are more dominant as their food source. Fruits and berries make up about 60% of their summer diet. Berry farmers suffer quite a loss of fruit but they also eat a great deal of harmful insects to make up for the damage. By the way, in the winter it seems as though robins are listening for worms by cocking their head to the side. Actually they are focusing one eye directly at the ground in order to see the slightest movement of grass or dirt and then quickly probing with their beak at that spot.
The robin is one of the earliest birds to nest in the spring and will often produce 2-3 clutches of eggs. Since they make a new nest for each clutch, they usually have the first nest in small fir or pine trees before the deciduous trees have put out all their leaves. The later nests are usually built in deciduous trees or bushes where the nest can be well hidden.
The scientific name of the robin is Turdus migratorius. This might seem like a derogatory name but “Turdus” is Latin for thrush and so the name means migratory thrush. Other local members of the thrush family are bluebirds, solitaire, and varied thrush. The varied thrush is also migratory and is found during the winter on the valley floor. It looks and acts like a robin but has orange breast feathers and orange stripes in its wings and lighter in color. It also has a distinct black band across the breast area.
Robins, thrushes and juncos along with our ever present jays, make up a good portion of our winter bird population and keep us busy filling the bird feeders, as well as entertaining us with their activities on the lawn.