We are in Lakeview Oregon, and the weather here is similar to yours. It is supposed to get down into the single digits in the next couple of nights. My Hummers all left in late September, but we had som really cold nights even then. I had a couple of things I did to keep the Hummers warm. There is an ant moat in my feeders that is right next to the section that holds the nectar, and it is just the right size to hold a Hothands handwarmer. It worked great, and puts out warmth for about 7 hours. I had to get up before daylight to beat the Hummers there,but it works! If you have to, you can duct tape it to the bottom of the feeder. The other thing I have read, is to make their nectar a 3 to 1 ratio instead of the usual 4 to 1. This gives them a little more energy and will help them put on a little more weight, so they can migrate. Hope this helps. I will be holding good thoughts for them.

Fran

Lakeview, OR,

zone 5

Thanks appreciate the suggestions. I heard Christmas lights may keep a feeder above freezing too. Got mixed info from a hummingbird site about changing the ratio to 3 to 1. Most sites don't recommend. Guess I'll get another feeder to switch out and get the handwarmers and lights ready!

Thanks for your good thoughts Fran!

After I read your answer about the ratios of nectar, I worried that I might be wrong, so I went to the Cornell's University Labs question and answer section, and found this:

Q. What's the best recipe for hummingbird nectar?

A. The sugar content of natural flower nectar varies, and is roughly comparable to sugar water mixtures ranging from a quarter to a third cup of sugar per cup of water. During hot, dry weather, when hummingbirds risk dehydration, it's best to make your mixture no stronger than a quarter cup of sugar per cup of water. But during cold, rainy spells, making the mixture a bit stronger, up to about a third cup of sugar per cup of water, will not hurt your birds and may help them.

thank you for prompting me to look this up! Never hurts to make sure.

Fran

Good news, Cornell U should know. I had read from a couple of the Audubon sites in Seattle and Portland... where it doesn't get as cold. They were concerned about dehydration.....but probably not as big a concern in the winter. Thanks for checking.

http://www.seattleaudubon.org/sas/LearnAboutBirds/SeasonalFacts/Hummingbirds.aspx

http://audubonportland.org/news/dec9-2013

Sounds like it's a short term solution. Please let us know how they are doing. They say it takes 5 to 7 days for them to put on enough weight to migrate. Hopefully, the weather won't get any worse. They can travel at 35 miles per hour, if they do decide to migrate, they could make it over the SantiAm pass in one day, and make it safely into the Willamette Valley. This would be a wonderful outcome. If not, you may have winter tenants. That would be an exciting adventure.

Fran

Anna's routinely overwinter in much of the PNW - they are pretty much considered year round residents. While less common year round in central OR than in more coastal locations, they can and do remain present all winter. My suggestion is keep your feeders up and filled as long as you see the birds, perhaps all winter long.

Hummers can take some pretty cold temps: "Anna’s also take advantage of the hummingbird’s motto “When things
get tough, the tough go to sleep.” A hummingbird in torpor can drop its
body temperature from about 40°C to about 9°C (from 104°F to 48.2°F) and
reduce its respiration rate from 245 breaths per minute to 6. It can
even suspend its breathing for up to five minutes. The metabolic rate of
an Anna’s during torpor can be 300 times lower than when in flight. The
savings are significant; they can help a hummingbird sleep through a
severe weather period.

A typical winter day might find an Anna’s sucking sugar, slowly
turning it to fat, and then going into torpor during the night, living
off the stored fuel. An Anna’s can gain 16 percent of its body weight
during the day and then burn it all off during a cold night. (Imagine
waking every morning 25 pounds lighter.) The fluctuation is extreme
enough without adding the energetics of flight. Regardless of the
season, awake and flying, a hummingbird is always just a few hours from
starvation.

So, unless you are following a mountain migration route south that
allows you to fly flower to flower as other hummingbirds do, it is best
to keep your metabolic engine parked in the garage as much as possible.
This is especially important if, during flight, your heart beats 1,260
per minute, by far the highest rate of any vertebrate. The alternative
is running out of gas long before you reach the wintering grounds.

Anna’s Hummingbirds trying to survive a cold winter also have another
item in their bag of tricks: They eat insects and spiders. They will
hawk flying insects, glean tree hoppers from leaves, probe crevices for
spiders, steal captured insects from spider webs, and pluck trapped
insects from tree sap. And you can assume that even more insects and
spiders await discovery in winter by hummingbirds that know where to
look."