Sunday, October 29, 2023

Nature: "Tis the season to spot dark-eyed juncos in central Ohio

 

A male dark-eyed junco snacks on poison ivy berries/Jim McCormac

Nature: "Tis the season to spot dark-eyed juncos in central Ohio

Columbus Dispatch
October 29, 2023

NATURE
Jim McCormac

“…there is not an individual in the Union who does not know the little Snow-bird…”
− John James Audubon (1831)

I suspect the great naturalist and pioneer ornithologist was optimistic in his estimation of junco familiarity. His “snow-bird” is now formally known as the dark-eyed junco, and back in Audubon’s time, people were far more attuned to the environment. Many if not most people probably were acquainted with the jaunty slate-colored sparrows.

Even today, with the popularity of bird feeding, lots of people know the junco. But in central Ohio, they’re primarily winter visitors. Juncos arrive on the first gusts of nippy fall winds from northern breeding grounds. I ran into my first dark-eyed juncos of fall just a few days ago, as nighttime temperatures began to dip towards the freezing mark.

Unlike many of its sparrow brethren, which are skulkers and shrinking violets, dark-eyed juncos are extroverted and easily observed. Adult males are a rich dark slate color above, with snowy underbelly and a pink bill. Their white tail feathers are often flashed conspicuously. Females and juveniles are more muted and infused with brownish hues.

There are plenty of dark-eyed juncos to see. The population, which breeds strictly in the U.S. and Canada, numbers about 630 million individuals, or about two juncos for every person. While juncos nest throughout the boreal forest of the northern U.S. and Canada, birds in northerly populations retreat southward in winter. These are the birds that we see at our feeders.

Ohio lies at the southern limits of the junco’s breeding range, with isolated nesters in the extreme northeast, especially Geauga and Lake counties. A small population breeds in Mohican state forest. But if you receive juncos at your feeders, the likelihood is that they hail from remote northern forests.

Over its vast North American range, the dark-eyed junco varies markedly in appearance. So much so that until 1973 it was divided into five species: gray-headed junco, Guadalupe junco, Oregon junco, slate-colored junco (our birds), and white-winged junco. Typical examples of each form are easily identified, but they all hybridize and produce fertile offspring, which is why the five were lumped into one species. The Oregon subspecies appears rarely but regularly in Ohio. Adults are recognizable by a black hood that contrasts with pinkish-brown flanks.

If you feed birds, you’ll almost certainly attract juncos. The jaunty little sparrows usually feed on the ground, often flashing their bright white tail feathers. Many species of birds that are habitual ground-foragers have white outer tail feathers. One explanation is that it presents a false flag to bird-hunting raptors like Cooper’s and sharp-shinned hawks. The raptor fixates on the junco’s bright tail feathers, seizes those, and the junco escapes, sans tail. But tail feathers grow back, and the junco lives to see another day.

The roughest of winter weather does not deter tough juncos. They essentially live in a sleeping bag of feathers, the dense down feathers shingled over by sturdy waterproof contour feathers. Juncos can stave off the coldest of Ohio temperatures. If snow covers food sources, they kick through it like little chickens to uncover the seeds.

Come mid-March, dark-eyed juncos start their northward journey. By May, nearly all of them have moved north, leaving us with to deal with a five-month junco hiatus. Throw some seed out for the snowbirds, and enjoy them will you can.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.

A female dark-eyed junco, or snowbird/Jim McCormac

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