Decades ago birds remaining in the Northeast in the winter almost exclusively survived on weed seeds and insects they gleaned from crevices in tree bark. Today, nearly one-third of American adults provide about a billion pounds of bird seed each year, to say nothing of suet, seed cakes, etc. Should we be worried about creating a population of food-dependent wintering birds? Studies suggest that this is not the case. Researchers (this is going to sound cruel) removed feeders from woodlands where Black-capped Chickadees had been fed for the previous 25 years, and compared survival rates with those of chickadees in a nearby woodland where there had been no feeders. They documented that the chickadees familiar with feeders were able to switch back immediately to foraging for natural foods and survived the winter as well as chickadees that lived where no feeders had been placed. Not only did the feeder-fed birds not lose their ability to find food, but research also showed that food from feeders had made up only 21 percent of the birds’ daily energy requirement in the previous two years. This is not to say that there aren’t negative aspects to feeding birds, such as window collisions, disease, house cats, etc., but one thing luring birds to our houses for a closer look doesn’t do is destroy their innate ability to find food. (Photo is of a Red-breasted Nuthatch.)
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Black-capped Chickadees tend to be early nesters, often as early as April, as they build their nest inside a cavity where it is sheltered from the cold. Chickadees rarely re-use a nest, so one might guess that this Black-capped Chickadee with nesting material in its beak in early July has a second brood on its way. However, it is unusual for Black-capped Chickadees to have a second brood of young after the first has fledged. If they lose the first brood, they sometimes will re-nest, but it’s more likely that this chickadee is just a late nester, as nest-building can and does occur up until mid-July. Both members of a pair excavate a cavity in a rotting tree, stump or post and then the female alone builds the nest inside the cavity. The foundation of the nest is usually made of coarse material such as moss. The lining consists of softer, finer material such as deer hair, rabbit fur, or in this case, an aging chocolate Labrador Retriever’s hair.
Even though black-capped chickadees are named for their chick-a-dee-dee-dee winter song, it is their so-called spring song which resonates most with many of us. It seems as if chickadees are immediately aware of when the days start to get longer, as their mating song begins as early as January. Sounding to some like “fee-bee” and others as “hey-sweetie,” this delightful song consists of two whistles, each about half a second long, with the second whistle a lower pitch than the first. Although these cavity nesters won’t actually be breeding until April, we will continue to be serenaded by their courtship song throughout the winter. As birdsong expert Donald Kroodsma so aptly describes this song, “It is the purest of whistles, this promise of spring.”
A smelly nest is a dead give-a-way to would-be predators, so most birds make an effort to keep their nest fairly clean. (In addition, if the nestlings’ down feathers get matted, they cannot assist in keeping the young birds warm.) While the young of some birds, such as raptors and herons, defecate at or over the edge of the nest as they age, the waste of many young songbirds is excreted in what is called a fecal sac – a nice, tidy bundle which the parents carry off and drop at some distance from the nest. Some species of birds actually eat their nestlings’ fecal sacs when the nestlings are very young, as the sacs still contain some nourishment.