Dark-eyed Junco: the winter bird that arrives on a schedule

The short answer

• In most of the northern and central United States juncos appear in the second half of October and are gone again by mid-April, tracking the first and last hard frosts closely.
• Millet and sunflower hearts are their top foods. Scatter them on the ground or on a tray no more than about 12 in high.
• Juncos will not cross much open ground. Put the feeding area within 6 to 10 ft of a shrub, hedge or brush pile and the flock will settle.
• The slate-gray eastern bird, the hooded Oregon bird of the West and several other regional forms are all one species, so the one in your yard depends on where you live.
• A winter flock runs a stable pecking order, and the lowest-ranked birds feed at the edges, which is why spreading seed over a wider area increases how many birds you hold.

Juncos keep a calendar. Write down the date you see your first one and you will find that next year's first date lands within about a week of it, and the year after that too. Almost nothing else at a feeding station is that predictable, and it is the most useful thing to know about the species.

The arrival window#

Juncos are short-distance migrants moving off a breeding range in the boreal forest, the western mountains and the Appalachian spine. They come down in stages behind cold fronts rather than in one wave.

The decision rule that makes this usable: when your overnight lows have been below freezing for three or four consecutive nights for the first time in autumn, check the ground under your feeder for the next week. The birds are responding to conditions north of you, so they usually show up either just before or just after your own first hard frost.

The reverse rule works in spring. Once your overnight lows stay above freezing for a full week, the flock is normally gone within ten days. People often report that the juncos vanished suddenly, and the reason is that they leave as a group.

Which junco is in your yard#

All of these are one species. They were split into several species in older books, which is why you will still hear the old names.

Every one of them is a small gray-and-white bird with a pale conical bill, dark eyes and white outer tail feathers that flash on take-off. If you get an unexpected form in the wrong region, it is worth a second look: a Slate-colored bird in California or an Oregon bird in Pennsylvania happens most winters somewhere.

Feeding them the way they want to be fed#

1. Hearts Top
2. Millet Top
3. Black oil Yes
4. Nyjer Yes
5. Cracked corn Yes

Millet and sunflower hearts head the list. Millet is the practical choice for volume because it is cheap, low-mess, and precisely the size of seed a junco takes in the wild; hearts are the choice if you also want the tray to serve finches and chickadees. Cracked corn works and costs less again, but it molds fast in damp weather, so keep it to what is cleared the same day.

Placement is where most people go wrong, so three rules with numbers:

1. No higher than 12 in. A low tray, a paving slab, or bare ground under an existing feeder. Juncos rate 4 out of 4 for ground use and will use a platform feeder or a broad hopper ledge, but the ground is the default.
2. Within 6 to 10 ft of cover. A hedge, a shrub, a brush pile of cut conifer branches, or anything they can be inside in one hop. Seed on open lawn 30 ft from the nearest bush gets picked at nervously and abandoned. A brush pile is the single highest-value addition to a winter yard, and it costs nothing: see native plants and cover.
3. Spread it wide. Scatter a cup of millet over 6 to 8 square feet rather than piling it in one dish. This is not aesthetics, it is arithmetic about the pecking order, covered below.

Clear the seed area of snow after a storm and re-scatter. In a heavy snow winter a junco flock will switch to whichever yard on the street has bare ground, and it will be the yard where somebody swept.

The pecking order you can watch from the kitchen#

Winter junco flocks run a stable dominance hierarchy. Adult males generally outrank females and young birds, and the same individuals win the same disputes day after day. You will see it as short, low-intensity chases across the ground, tail-spreading displays and birds displacing each other from a good patch of seed.

The practical consequence is the spreading rule. A single dish is a monopolisable resource: two or three high-ranking birds hold it and the rest of the flock waits in the hedge. Seed spread across several square feet cannot be defended, so subordinate birds feed at the same time and your yard supports a bigger flock on the same weight of seed.

Other things worth knowing about how they behave:

• Flock size runs from 6 to 30 in most yards, often with white-throated sparrows, tree sparrows and the occasional cardinal mixed in on the ground.
• No caching. Juncos eat what they find. There is no hoarding behavior to allow for.
• Time of day is heavily weighted to the first hour of daylight and the last, with a steady trickle between. In hard cold, the dawn feed can be almost the whole flock at once.
• Approach is by hopping, both feet together, with a light scratch and a peck. They do not dig deeply the way a towhee or a white-throated sparrow does.
• They tolerate people well. A junco flock will feed 10 ft from a window, which makes them the best species for a first-winter window feeder view, provided the glass is treated for strikes.

If the juncos are not coming#

Work down this list before changing your seed.

It is too early or too late. Check the arrival table above. Half the reports of missing juncos are simply September.

There is nothing on the ground. A yard fed entirely from hanging tubes offers a junco nothing it recognizes as food. Scatter millet and check again in three days.

Nowhere to escape to. No hedge, no shrub, no brush pile. Juncos are prey birds that feed in the open, and they compensate by never being far from cover.

Cats. A ground-feeding flock will abandon a yard that a cat patrols, permanently. There is no seed answer to this one.

You live where they breed. In the Rockies, the Sierra, the Cascades and parts of the Appalachians the local birds move upslope to breed rather than out of the region, so summer absence at low elevation is normal.

Deep snow with no clearing. They will move to a yard where the ground is workable. Sweep a patch and re-scatter after each storm.

If none of that applies, run the general checklist in no birds at my feeder, and see winter bird feeding for the whole cold-season setup that a junco flock slots into.

Frequently asked questions#

When do juncos arrive for winter?

In the northern and central United States, usually between about 10 and 31 October, with the bulk arriving in the last ten days of the month. Further south, from the mid-Atlantic through the Southeast and the southern Plains, first birds are typically in the first three weeks of November. The trigger is weather to the north of you rather than in your yard: a run of hard frosts and the first significant cold front push them down. Keep a note of your own first date and it will repeat within about a week most years.

What do juncos eat at feeders?

White proso millet and sunflower hearts rate top-tier, with black oil sunflower, nyjer and cracked corn all taken readily. Millet is the cheapest and the most reliably effective, which makes juncos one of the least expensive birds to feed. They largely ignore suet, peanuts and mealworms. Because they are ground feeders, presentation matters as much as the seed: the same millet in a hanging tube will go untouched while a handful scattered under a shrub is cleaned up in an hour.

Why are juncos called snowbirds?

Because in most of settled North America they appear at the start of the cold season and leave when it ends, so their arrival has long been read as a sign of coming snow. The name is older than the field guides. It is also a fair description of the eastern form's plumage: slate gray above, white below, with the field mark often described as gray skies above and snow below.

Is an Oregon Junco a different species from a Slate-colored Junco?

No. They are regional forms of one species, the Dark-eyed Junco, and were once treated as separate species. The slate-colored form is the gray bird of the East and the boreal forest. The Oregon form, with a dark hood contrasting against a warm brown back and buff sides, is the western bird. Pink-sided, Gray-headed, Red-backed and White-winged forms occupy other parts of the West. All of them use feeders the same way.

Why do juncos feed on the ground and not on my feeder?

It is how they forage in the wild: hopping through leaf litter and grass, picking small seed off the surface. They can and do use a low tray or a wide hopper ledge, but they will not hang from a port or perch on a stub the way a finch does. Put a tray no higher than about a foot off the ground, or simply scatter seed on the bare ground beneath your main feeder, and they will use it immediately.

What are the white feathers on the sides of the tail for?

Signalling. When a junco flushes it spreads its tail and the white outer feathers flash conspicuously. The flash works both as an alarm to the rest of the flock and, most likely, as a signal that confuses a pursuing predator about the bird's exact position. It is also the fastest way to identify a small gray bird that has just left the ground in front of you.

Sources and further reading

1. Dark-eyed Junco Cornell Lab of Ornithology, All About Birds Regional forms, measurements, range and feeding behavior
2. Feeding Birds Cornell Lab of Ornithology, Project FeederWatch Seed preferences and ground-feeding presentation
3. Dark-eyed Junco National Audubon Society Guide to North American Birds Seasonal distribution and habitat
4. Birds Canada Birds Canada Canadian breeding range and winter feeder programs