Wild Side: Song sparrows

Small and drab, but admirable and resourceful.

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A male song sparrow singing from a wire in Oak Bluffs. — Matt Pelikan

Like most birders, I’m fond of wandering rarities, brightly colored species, and large, charismatic species — the kinds of things that draw hordes of observers and photographers and sometimes even make the leap into the consciousness of the non-birding world.

But I’ve also always liked the small, drab, common birds that make up the vast majority of my interactions with the avian world. There’s something admirable about the resourcefulness needed for a wild species to persist in large numbers in a human-altered world. And the fact of commonness and proximity translates into opportunities for frequent or prolonged observation — a chance, that is, not just to see something but to get to know and understand it.

Foremost among this class of avian acquaintances would be the song sparrows that inhabit my neighborhood. An array of small, nearly suburban lots on the outskirts of the Oak Bluffs megalopolis, the area offers surprisingly congenial conditions for these sparrows, which are numerous and conspicuous neighbors.

Though various populations of song sparrows are migratory, some or all of my local birds stay put through the winter, frequenting the neighbors’ feeding stations and sometimes poking around the meadowlike shambles that was formerly our lawn. In late February and March, these birds, silent and rather cryptic through the winter, start to reclaim their positions of prominence, with the males giving their complex, melodious songs more and more frequently.

A widespread and much-studied species, the song sparrow flourishes in an incredibly wide range of conditions. Breeding at varying densities in everything from arid lands to marsh edges, these birds are common through most of the United States and Canada in the summer, and partial seasonal withdrawal brings them to southern regions outside their breeding range in winter.

Across this vast range, the species varies somewhat in color and size. But these average-size sparrows are always recognizable by their streaked breasts featuring a strong central spot and a strong “malar stripe” — an elongated triangular marking extending downward from the lower jaw.

Their songs are highly variable, with each male possessing a lifelong repertoire of half-dozen or so song variants. This variation makes a useful mnemonic device impossible — no single English phrase comes close to capturing all the variety. But the songs are invariably sweet and musical, and they rely largely on intervals that register as musical to the human ear. “Song sparrow” is truly an apt name.

Equally useful for identification purposes is the song sparrow’s subtle but distinctive call note: To my ear, is sounds something like “chimp! chimp!” and is somehow both cheerful and inquisitive. Song sparrows give this note frequently, to maintain contact with each other or in response to nearly any kind of minor disturbance.

Highly evolved for singing, this species seems to use its vocal powers to make its social life efficient. Individual males have been shown to acquire their song repertoire early in life, mainly by listening to their father and other male birds in the area. Interlopers from elsewhere, singing different songs, are instantly recognizable (both to the sparrows and to a human observer who pays close attention), and may draw a defensive territorial response from locals. But otherwise, song alone seems to suffice for dividing the world up into song sparrow territories. Males sing frequently, but rarely seem to indulge in the sort of physical squabbles that many other species use to sort out territorial issues.

Comfortable nesting close to houses and other structures – evergreen foundation plantings are a frequent nest site — song sparrows are known to adjust their territory size to the amount of resources present. My residential neighborhood, offering year-round feeding stations as well some mature vegetation and weedy vacant lots, seems pretty productive from a song sparrow’s perspective: Each local male seems content with an acre or less of domain. And while these birds or their eggs and nestlings surely fall prey to cats, hawks, crows, and skunks, persistence pays off: The sight of an adult song sparrow stuffing insects into a fledgling is an annual sight in my yard, and the local population clearly breeds successfully enough to keep numbers stable.

For the first decade or so of my 20 years on the Vineyard, the local song sparrow population (at least as represented by prevailing song types) seemed to be quite stable. One male, recognizable but evidently not at all handicapped by a crumpled foot, held court for four years, which is a very long life for a small songbird. And for a half-mile or so in any direction, the same mix of song types dominated.

Things have gotten less tidy of late. Perhaps mortality rates have increased, creating more opportunities for newcomers to take over a territory. But I’m hearing more song diversity and noticing fewer instances of particular birds persisting across multiple seasons. Although something has clearly changed for this species, I’m not worried. Numbers of song sparrows remain high, and it’s clear that whatever is going on just constitutes one more minor challenge that this versatile species is well equipped to meet.