October is sparrow season on the Vineyard, and indeed throughout southern New England. This is the month when all the sparrow species that occur here regularly can be found, and when the odds are best for encountering rare vagrants.
A half-dozen sparrow species nest regularly on the Vineyard; a few of these, like grasshopper sparrow and saltmarsh sparrow, are scarce due to their strict habitat requirements. Others, like the song sparrow, nest pretty much everywhere. Like most songbirds, sparrows feed heavily on insects during the breeding season. But they are well-adapted to eating seeds, which lets them flourish in cold weather, after most warblers and flycatchers have moved south.
In fall, something like 15 sparrow species occur here more or less annually (I’m not counting towhees and juncos, which are sparrows in taxonomic terms, but don’t have the cryptic, streaked plumage of typical sparrows). The Island has records for a few more species, so sparrows are invariably well-represented on autumnal birding checklists.
Brown and streaky, sparrows are not pretty birds, at least not in any conventional sense. But they tend to be active birds, making them fun to watch, and I suppose I enjoy the challenge of identifying them. Seen well, sparrows all have distinctive markings that reveal their identity. But especially during fall migration, sparrows are skulking birds of thickets; getting that good look is not easy, and often all you have to work with is a brief glimpse of a random body part. It takes some skill, knowledge, and luck to piece together a firm ID.
I like all our sparrows, but for now, let’s consider just one, the chipping sparrow. A small, round-bodied, long-tailed bird, the chipping sparrow, once out of its juvenile plumage, always shows some version of a reddish cap, a white band over the eye, and dark line running right through the eye. The pattern is obvious on adults during the breeding season, more muted on fall birds of all age classes.
The chipping sparrow ranks among our more common nesting songbirds, with hundreds of pairs undoubtedly present on the Island during a typical summer. And this bird’s habits make it seem even more common than it truly is.
For one thing, this species is a bird that is unusually comfortable around humans. Or perhaps more accurately, human-created habitats tend to offer conditions that this bird finds attractive. The chipping sparrow is a bird neither of deep woodland nor of open fields or grassland. Rather, it favors areas where those two classes of habitat meet or mingle. A yard will do fine for a chipping sparrow pair; so will an old pasture, grown up with shrubs and tall weeds.
For nesting, chipping sparrows clearly prefer conifers. On the Vineyard, that often means either pitch pine or red cedar, though ornamental evergreens work just fine. They can nest in deciduous trees, too, or at least I’ve found territorial pairs in areas devoid of conifers. Generally built less than a human’s height above the ground, chipping sparrow nests are marvels of meticulous construction, tightly woven baskets of grass lined with finer stems or fiber. Horsehair, if it’s available, is an amenity chipping sparrows can’t resist including in their nests.
The apparent prevalence of chipping sparrow as a nesting species is also boosted by this bird’s vocalizations. It’s a talkative species, with family groups or flock members staying in touch with call notes frequently given: an assertive “chip,” which gives this bird its common name, and a thinner, fainter, “tsee” note. But it is really the song that creates the impression that this bird is everywhere. A prolonged trill on a single pitch, the song is instantly identifiable, loud, and often given from an elevated perch that helps the sound disperse.
As the summer winds down, chipping sparrows grow quite gregarious. Family groups seem to remain together after the young have fledged, and several families may aggregate into loose, informal flocks. Through late August and September, these groups can turn up nearly anywhere, but may be most evident along roadsides. I don’t know what the attraction is — grit? The seeds of roadside weeds? — but small flocks scattering as cars approach are a common sight.
As fall begins and we inch into October, it seems like our breeding birds head out, or at least relocate to less obvious settings. Anyway, there are usually a few weeks in early autumn when chipping sparrows grow rather scarce. But transients quickly take the place of our breeding population, with anything from single individuals to flocks of two dozen or more a common sight.
Numbers decline into winter, but the chipping sparrow turns up regularly, and sometimes plentifully, on Christmas Bird Counts. CBC numbers have increased fairly steadily over the past few decades. A few birds make it through the winter here, and breeders return in mid-April, their distinctive song going abruptly from nowhere to everywhere. I’m always happy when they arrive.