Leaving a hummingbird feeder up in winter

The myth, dealt with first

The belief that leaving a feeder up will stop hummingbirds migrating is the single most persistent piece of misinformation in this hobby, and it is wrong.

Boise State University’s Intermountain Bird Observatory addresses it directly: “This is actually a myth! Hummingbirds (and many other long-distance migrants) use day length to decide when to migrate.” The trigger is photoperiod — an internal calendar keyed to the shortening of the days — not the availability of a meal. North Central Washington Audubon states the same conclusion for the species most people are asking about: feeding Anna’s Hummingbirds during the winter will not keep them from migrating.

The Observatory goes further and points out the upside: leaving feeders up can actually help stragglers who are running late on migration. A bird passing through in November is not late because of your feeder. It is late for its own reasons, and your feeder may be the difference.

We cover the same ground from the autumn side in when to take hummingbird feeders down.

Who this page is actually for

Winter feeding is not a national practice and we are not going to pretend it is. It comes down to which species is in your yard.

Anna’s Hummingbird is the reason this page exists. Unlike Rufous, Calliope and Black-chinned Hummingbirds, Anna’s does not head to Mexico for the winter. It holds territory year-round across much of the Pacific coast and has been expanding inland — the Intermountain Bird Observatory notes Anna’s expanding into Idaho. If you are on the West Coast or in the interior West and seeing hummingbirds between October and March, they are almost certainly Anna’s.

Most of the East is a different story. The Ruby-throated Hummingbird that dominates the East migrates, and by deep winter there is genuinely nothing to feed. Leaving a feeder up through late fall is still worthwhile for stragglers — it costs you little and it is the reason we suggest waiting about two weeks past your last sighting — but a January feeder in Vermont is maintenance without a beneficiary.

The Gulf Coast and Southwest sit in between, with wintering individuals of several species turning up in numbers that vary year to year.

Our regional timing table is on hummingbird migration by region, and the spring side is on when to put feeders out.

The actual problem: keeping it liquid

Nectar at 4:1 freezes a little below the freezing point of water — not much below. On a cold night a feeder becomes a solid block, and a bird that has burned its reserves overnight arrives at dawn to find nothing available. Dawn is precisely when it needs the feeder most.

The Intermountain Bird Observatory lists heated feeders, brooder heat lamps, and a heated dog bowl with a saucer-style feeder as workable systems, along with a caution worth repeating exactly: “These systems keep feeders defrosted. They cannot melt a frozen feeder.”

That sentence is the practical heart of this page. Heat sources here are for prevention. If you wait until the feeder is solid and then switch something on, you have lost the morning. Whatever method you choose has to be running before the freeze, not after it.

Note also which feeder shape that guidance assumes: a saucer. A shallow dish sits flat on a heated surface and the whole reservoir is close to the heat. An inverted bottle stands tall with most of its volume well away from anything warm, and the part that freezes first is the narrow neck where the nectar has to flow. If you are setting up for winter, the saucer design is not just easier to clean — it is the shape that works with a warm surface at all. See saucer vs bottle.

The low-tech method, and its one requirement

You do not have to buy a heated feeder. The simplest approach is rotation: keep two feeders, leave one out and one indoors, and swap them when the outdoor one starts to thicken. The indoor one goes out already liquid; the frozen one thaws on the counter.

The requirement is in the first word — two. A single feeder brought inside to thaw is a feeder that is not available to a bird for however long thawing takes, which on a cold day is most of the useful daylight. This is one of several reasons we think a second feeder is the best cheap upgrade in this hobby; the others are in how many hummingbird feeders you need.

Two further things that help, both free:

• Move it closer to the house. A wall gives off radiant heat, blocks wind and often sits under an eave. A window feeder is the extreme version of this and it is why the Jewel Box is on the picks above.
• Put it in the morning sun. The reverse of the summer rule. In July you want shade so the nectar does not cook; in January you want early sun on the feeder so it thaws when the birds need it.

What not to do: do not add anything to the nectar to lower its freezing point. Not alcohol, not glycerin, not extra sugar. A stronger mixture is not antifreeze, it is a worse solution — North Central Washington Audubon states that pure cane sugar mixed 1 part sugar to 4 parts water is the safest and most used recipe, and the ratio page explains why stronger is not better. The full list of things that do not belong in a feeder is on what not to use.

Cleaning does not stop for the season

This is where winter feeding most often goes wrong, and it is a genuine welfare issue rather than a tidiness one.

Cold slows fermentation, so the change interval does stretch compared with July. It does not disappear. North Central Washington Audubon is unambiguous that keeping your feeders clean all year is extremely important, and a feeder that sits out for a fortnight because it is cold outside is still growing something.

There is also a specifically wintery failure: repeated freeze-thaw cycles concentrate and dilute the mixture unevenly and leave residue in the ports, and a feeder you are handling in gloves at dusk is a feeder that gets a cursory rinse rather than a wash. The rotation method helps here too, since the feeder that comes indoors is already at the sink.

Keep the same routine, stretched sensibly: full disassembly, hot water, a port brush, rinse, dry. The method is on how to clean a hummingbird feeder and the cadence logic is on how often.

Once you start, finish

The Intermountain Bird Observatory’s guidance is direct: once you have an Anna’s committed to your feeder, they do not recommend taking it down unless temperatures are above freezing.

That is worth thinking about before you hang a feeder in November rather than in the middle of a January cold snap. A bird that has built its winter territory around a reliable food source, in weather where natural nectar and insects are scarce, is relying on something you can switch off. This does not make winter feeding a trap — the research picture is that Anna’s persist in areas regardless of individual feeders — but it is a reason to be honest with yourself about whether you will keep it up through the worst week of the year.

If the answer is no, take it down in the fall on the normal schedule and start again in spring. That is a perfectly good way to feed hummingbirds, and it is what most of the country does.