The robin that Loie found in my yard during the Great Backyard Bird Count on Feb. 14 was most likely not a returning spring robin. It was one of several that usually winter in the area. There were 30 American robins reported on the Christmas Bird Count last December.
These are birds that probably nest much farther north and winter here. They survive the cold in sheltered valleys and feed on juniper berries and by foraging beneath the ground juniper shrubs where there are a great many old fallen berries and a thick layer of duff in which they can often find some wintering insects. They are quiet and secretive, so we seldom know they are around. Occasionally, they can be heard making their little, low exclamation of “pleet,” which is sometimes followed by a few low “tut, tut, tuts.” These are quiet call notes usually uttered late in the day.
Spring robins may arrive as early as February but are more usual in March or April. They usually arrive after the first spring rains bring the earthworms up to the surface, and they are seen boldly running about on lawns and singing from nearby treetops to attract a mate and warn intruders away from their territory.
Bluebirds also return in early March, usually surviving through several spring snowstorms. They, too, eat frozen juniper berries and any insects they can find in sheltered places. Although they seldom lay eggs before the first week in May, they stake out and defend a nest cavity long before that. Because nesting cavities are so scarce, they claim any cavity they can find, in an old tree, a house soffit, a fencepost or a nest box, soon after their return. Many skirmishes follow to defend their chosen site, and the female slowly builds a large grass nest. When it has finally warmed up sufficiently for insects to be about, the female lays from four to six eggs, which means the young usually hatch about the fourth week of May or the first week of June.
The Evergreen Naturalists Audubon Society for this reason sells birdhouses (nest boxes) every year at Safeway and King Sooper stores on or about the first weekend in March. This year the sale will be on March 7 and 8, with sales at King Soopers in Bergen Park, Evergreen Safeway and if possible at both stores in Conifer.
The new bluebird box introduced last year has proven to be very successful and will be on sale at $25 each. House wren and chickadee boxes are smaller and priced at $20, and the large flicker boxes are reasonably priced at $30. It’s a good idea to have one of these around to put up in a hurry if a flicker begins to make a hole in your house. If you quickly put up a box over his chosen spot, he will usually use the box; it will save the birds a good bit of hard work, and it will save your house. The flicker boxes come with a small amount of sawdust and wood chips to place in the bottom to meet their requirements for nesting.
Chickadees and nuthatches will also use bluebird nest boxes. Bluebirds will nest anywhere from 4 to 20 feet above the ground and should be protected by predator guards. Pygmy nuthatches prefer houses higher up, 30 feet or so and among the trees, while bluebirds will use lower boxes and need an open meadow in which to hunt for insects.
Tree swallows and violet-green swallows will also use bluebird boxes and will fight to take one away from bluebirds. However, they too prefer boxes higher up that they can sweep into from the air. Try placing some higher for swallows out in the open and some lower at the edge of the meadow for bluebirds.
Robins do not nest in boxes or cavities but will build on an open-fronted shelf. Just a shelf may do, but one with two sides and a back gives them more protection from spring snow and cold winds.
Don’t miss the nest box sale this weekend, and get there early, for they often sell out. Give our birds a place to nest, and remember: This is the Audubon Society’s main fund-raiser for the year. It provides the money for many great projects.