With the usually temperate Pacific Northwest battered by fierce winter storms, there’s a lot of concern about how the resident Anna’s Hummingbirds are handling brutal temperatures and frozen feeders, and what their human hosts can do to help them survive.
One way to help is to use a slightly stronger feeder solution. Many people, myself included, have switched to a ratio of 3 parts water to 1 part sugar for all or most of the year. The sugar concentration (about 23% by weight) is closer to the average sugar content of hummingbird flower nectars (about 25%) than the standard 4:1 recipe (about 18%), and it has the advantage in winter of freezing a little more slowly.
It’s important not to go overboard, because more is not necessarily better. Sugar solutions sweeter than 3:1 can be syrupy enough to interfere with feeding efficiency, and this effect is magnified as temperatures plunge. There’s also the issue of dehydration, since nectar is a hummingbird’s main source of water (especially when everything else is frozen).
Even 3:1 will freeze if the temperatures dip low enough, but some winter hummingbird hosts have reduced the need for switching feeders by placing them next to a window (the more poorly insulated the better), inside an open shelter made of plywood, or under an outdoor-rated heat lamp.
If you make the switch to 3:1, you’ll need to adjust your expectations a bit. Since it contains more calories per drop than 4:1, your birds will not have to visit as often. It may look as though they’re avoiding the feeder when actually they’re just feeding more efficiently.