Friday, 29 January 2016

Wintering Fox Sparrows


Nature Notes for January 29, 2016

A flock of juncos flushed from the road ahead of us. Their white outer tail feathers flashed their identity. Of course, they dived into the bushes at the side of the road as we approached. But wait. That bird in the nearest bush isn’t a junco. It’s a Fox Sparrow and it doesn’t have a tail. It must have had a near miss with a predator.  A more thorough scan of the flock found another Fox Sparrow, this one with its tail intact.

                                     Photo © Rob Lonsberry Photography


There are four recognized forms of Fox Sparrow and they inhabit different geographic regions of North America. From DNA studies, there is evidence that they should be split into four separate species, but that has not happened yet. The form that occurs in eastern North America is the Red Fox Sparrow and that is the one that is seen in Northumberland County.

Fox Sparrows are one of the largest North American Sparrows. The Red Fox Sparrow has a gray head, with rufous red on its head, wings and body, a streaked breast, with a red spot in the centre of the breast. They are quite chunky birds and might be mistaken for a rather large Song Sparrow because of their streaky plumage and central breast spot.

Fox Sparrows are seen mostly as migrants in this area, but a few do spend the winter. In both spring and fall migration, they are often found singly or in small flocks, sometimes among flocks of other sparrows. During migration, they are often found in wood edges and woodlands that have a brushy understory.

Although a few persist through the winter, most migrate to the southeastern U.S. They are rarely found on local Christmas Bird Counts and usually at bird feeders. A number of years ago, I participated in a Christmas Bird Count just north of New York City. I was astonished to find ten Fox Sparrows on a short section of the trail that I was assigned. They are a much more common wintering bird in the New York City area than they are in Northumberland County.

The Red Fox Sparrow nests in Ontario, but most densely in the Hudson Bay Lowlands. Most nesting is well north of Cochrane. They are a taiga species, but they will also nest in the brushy tangle that grows up following logging.  Their preferred habitat is a dense deciduous thicket (commonly alders or willows), dwarf spruce or fir and bogs.

Most Fox Sparrows nest on the ground. Their nest is a bulky cup of twigs, rootlets, lichens and grasses, lined with finer grasses, fur and sometimes feathers. The nest is often placed among mosses, grasses or Labrador tea.

Their song is quite unsparrow-like, with a series of loud, clear, ringing whistles. Sometimes we are lucky enough to hear this song in the spring, but mostly we hear the loud “smack” of their alarm call.  

They feed on the ground, where they are often detected by their scrabbling around in dead leaves. Their foraging technique is a two-footed scratch. That is, they jump with both feet at the same time to uncover the insects and seeds on which they feed. When we see them in migration and in winter, they feed on a variety of foods including fruit, spiders, millipedes and buds, in addition to insects and seeds. They are thought to feed their nestlings mostly insects.

For once, it can be reported that Fox Sparrows are not a species in decline, probably because most of them nest far enough north to be unaffected by human activity. In fact, intense logging may provide nesting habitat for this species in the shrubby tangles which regenerate following logging.

Perhaps, come March, readers will be fortunate enough to find a Fox Sparrow at a backyard feeder, stopping in for some food on its way north.