For the Birds Radio Program: Last Hummingbirds of the Season
Every year around Labor Day weekend, people start taking in their hummingbird feeders for another year. It certainly seems like the right time—we go from peak hummingbird activity in the middle of August to virtually no activity at all as September begins. Virtually all the hummingbirds we see during the last half of August are adult females and immatures, none of which have a ruby-red throat. Adult male hummingbirds pretty much vanished from the northern parts of their range in early August, though this year I was lucky enough to see a straggler on August 30 in Duluth. I was still getting four or five different immatures or adult females coming to my feeder every day through September 3. When they disappeared, my feeder was suddenly empty most of the time. It would have seemed as if every hummingbird was gone for good, except that I happen to have my computer desk right at my feeder window, and so I notice when migrants pass through and grab a quick meal. Sure enough, at least through writing this on September 6, I’m still getting at least a few individuals passing through each day. We haven’t had a frost yet in Duluth and there’s plenty of jewelweed here and there, so hummingbirds from further north find both insects and nectar as they move along. But individual flowers don’t bear nearly enough nectar to fill up a hummingbird—they take little sips as colorful flowers attract their attention during migratory flights, and when they notice a feeder, they make a beeline and completely fill up. Sometimes when a migrant arrives at my feeder, it fills its entire crop and stomach and then sits to rest in a nearby box elder branch as it digests its big meal, snoozes, and preens. After 15 minutes or so, it takes another big drink and moves on. Unless a hummingbird is emaciated and hasn’t found food in many miles, a feeder doesn’t hold it for long. As we get into September, the only stragglers at all tend to be late-hatching hummers that weren’t bulked up enough to leave until late. These young birds are at risk of not surviving the migration after flowers and insects disappear. Keeping hummingbird feeders with fresh sugar water available through September and October won’t help more than a handful of hummingbirds at most. But the help a feeder can give any individuals that do stop is well worth the effort. The latest I ever have had Ruby-throated Hummingbirds at my own feeder in Duluth was late October. That one drank fully and then moved on. The calories it got at my feeder would have fueled at least a few miles.
In 2004, I left my hummingbird feeder out all the way into November. And on November 16, through the closed window I suddenly heard a familiar hum and looked up to see a hummingbird! This one wasn’t a Ruby-throated Hummingbird—it was a Rufous Hummingbird—a species that breeds in the northern Rocky Mountains. Most of them winter in Mexico, but more and more individuals are migrating southeast, and surviving winter as far north as Ohio. Mine had apparently gone a long way without encountering a bird feeder—hardly surprising in November, but hard on a long-distance migrant with over a thousand miles to cover before she got anywhere near a place she could survive the winter. I put out extra feeders and she stuck it out in my yard for two full weeks, surviving a blizzard and a night when temperatures dropped to 6 degrees, finally heading out on a sunny, mild December 3.
Keeping out hummingbird feeders through late fall is a gamble—we’re not likely to encounter hummingbirds at all after mid-September. But after my own autumn encounters with hummingbirds in the past, I’m going to keep my feeder out and the sugar water fresh.