Ruby-throated Hummingbirds

Nature Notes for September 2, 2011

I heard the squeaking sound as I scanned the garden this morning. A Ruby-throated Hummingbird was complaining that I wasn’t prompt enough at getting the feeder out.

There are flowers it can nectar on: three hanging fuchsias, a few late flowers on the weigela, the hosta. In natural areas at this date, they are often found nectaring on the orange flowers of jewelweed in damp areas along streams and the edges of marshes. Earlier in the season, they feed on different flowers such as forget-me-not, currants, scilla and maple flowers.

As well as nectar, hummingbirds feed on very small insects – aphids, thrips, mosquitoes – as well as small spiders and spider eggs. They are sometimes seen flycatching. That is, they perch on a branch and make forays into the air to capture passing insects. They also glean small insects from tree leaves and buds.

They are known to feed at Yellow-bellied Sapsucker “wells”. These woodpeckers drill rows of small holes into living trees. Like the woodpeckers, hummingbirds feed on the sap and also on the insects trapped in it.

They need extra food now to store energy for their long migration to Mexico and Central America. Ruby-throated Hummingbirds are known to fly across the Gulf of Mexico.

Most will leave our area during the last week of August and the first week of September. A few may hang around until early October.

Hummingbirds occur only in the New World. There are about 320 species of hummingbirds, but the only one which breeds in eastern North America is the Ruby-throated.

The male is named for his red throat. This red is a iridescence, not a pigment. It only appears red if the angle of the light is just right. The back and sides of both sexes is green. The female has a pale throat. Young males may appear almost the same as the females, although a few individuals may have a red feather or two if the observer is lucky enough to get a close look.

Hummingbirds do not pair up to raise their young. Male hummingbirds defend a feeding territory during the breeding season. The males try to mate with any female which enter their territory. The female then returns to her own territory to build a nest, lay the eggs and raise the young by herself.

The male will defend his territory from all comers. In our garden, I have watched him chase Black-capped Chickadees, European Starlings and sometimes even Blue Jays.

The nests are incredibly small. A penny will fit very nicely into one. They are made of plant down, stuck together with spider web and covered on the outside with  lichens. The nest looks very much like a small bump on a branch.

Ruby-throated Hummingbirds typically lay two eggs, each about the size of small pea. They may nest twice in a season.

If you see a hummingbird in late October or November, it might not be a Ruby-throated. Take a very careful look at it. That is the time when vagrants from western North America sometimes turn up. The most common vagrant is the Rufous Hummingbird.

Several years ago on a Christmas season visit to New York, I saw three species of hummingbirds. One was probably a Ruby-throated. One was a Rufous Hummingbird. The third was a Calliope Hummingbird. None of these should have been there at that date.

To learn more about hummingbirds, check out www.ontariohummingbirds.ca