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by Kevin Strauss
It happened last week in my yard. Hopping across the dead grass on my lawn was that orange-red herald of spring, the American robin. Few phenological (nature calendar) events are as clear-cut as the first robin of spring. The birds that I saw were undoubetly males, since the males arrive earlier than females and set up breeding (and singing) areas. While male and female robins look similar, about 10 inches long with a dark brown bak and wings and an orange-red to red belly, females have paler colors than the showy males.
Robins are considered short distance migrators because they fly south for the winter only far enough to find fruits to eat. If it is a mild winter, they don't travel as far to the south. But when spring comes, researchers have noticed that the the impatient male robins seem to move north right along with the 37 degree Farehneit isotherm, in effect, riding the warmer southern winds to the north. And some robins travel a long way to the north. Their summer range reaches almost to the arctic circle in northern Alaska and northern Canada.
One of the reasons that we are so familiar with robins is that they prefer the same kinds of habitat that we do: short lawns and trees. Robins also nest where it is easy to see them, between five and fifeteen in the branches of trees or shrubs.
The male's cheerie-up, cheerie-oh, cheerie-up, cheerie-oh starting early each moring is one of the first spring bird calls most people notice.
Starting in mid- to late-April, after the females arrive, the pair will build their open-cup nest out of sticks, grass and mud. It seems that while the male will help collect materials, the female does the actual construction. After that, the female will lay 3-4 robin's egg blue eggs. The female will incubate the eggs for about two weeks and then both the male and female set to work feeding the nestlings. As any parent knows, children eat a lot. In one study, a robin nestling was seen to consume 14 feet of worms in one day! Finding food is a lot of work for those two harried parents. About two weeks later, the nestlings have fledged and two weeks after that, the speckled juveniles are on their own. Robins mate from April to July and may have as many as three broods in a season.
While I often think of robins as being primarily worm-eaters, I was surprised to learn that much of their diet is from fruit trees, especially in the fall, winter and early spring, when worms are less available. We often associate robins with a worm diet because worm-hunting is when we most often see robins on our lawns.
This week the robins in my yard are hopping around cocking their heads to the side. It looks like it is listening for a worm, but actually, it is turning its head to the side so it can get a better look at the ground. A robin's eyes are on the side of its head. So it is watching for small movements in the soil and grass that tell it that a worm is tunneling near the surface. In addition to worms, robins also feed on grubs (beetle larvae) and caterpillars.
So take time to look outside and watch these lawn hunters and spring song singers at work.
The Ely Timberjay
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