It’s hummingbird season

Adult male ruby-throated hummingbird (Photo provided — Ian Davies, Macaulay Library, Cornell Lab of Ornithology)

I’ve always been fascinated by ruby-throated hummingbirds (Archilochus colubris), the only hummingbird species to regularly breed in eastern North America.

They’re small hummingbirds with slender, slightly curved, black bills, fairly short wings that don’t reach all the way to their tails when sitting and strikingly radiant iridescent feathers that change in intensity and hue, depending upon the light and your angle of view. All ruby-throated hummingbirds — males, females and immature birds — flaunt bright emerald or golden-green on their backs and crowns, with a dull white or pale gray breast. Only the male brandishes the intensely lustrous ruby-red throat for which they’re named.

No other bird flies quite like the hummingbird, whether zooming along at speeds of 25 to 30 miles per hour for long distances (50 mph to escape; more than 60 mph to dive) or dashing from one bloom to the next, often stopping in an instant and hanging motionless in midair or adjusting their position up, down, sideways, and backwards with astonishing precision. They can even execute somersaults and/or fly upside-down for short distances.

These remarkable little stunt-flyers get their name from the whirring sound their wings make while beating at astonishing speed, more than 50 times per second. And during courtship flights, in which the males fly and dive up and down in arc patterns, that velocity may climb to about 200 beats per second.

The hummingbirds’ unique anatomy reveals the key to their remarkable maneuverability. Their wings are attached to the sternum in tiny ball-and-socket joints that allow the flexibility of wing movement required for their inimitable flight. And, although their skeletons contain some solid bones, most are extremely porous or, in the case of their wing and leg bones, hollow.

This has allowed hummingbirds to develop their exceptional ability to forage while hovering, which contributes to the pollination of many plants and gives them access to food sources that aren’t available to other birds. Wildflowers typically grow too high off the ground for standing birds to reach and are too flimsy to support perching birds.

In order to sustain such rapid wing beating and energetic movement, hummingbirds must maintain a metabolic rate (the amount of energy expended in a given unit of time) that is the fastest of any warm-blooded animal on the planet (roughly 30 times that of humans) and requires that they consume at least half their body weight in nectar, either from suitable flowers or from sugar water solutions in feeders, every day. They also eat insects and spiders, which provide necessary protein and other nutrients, snatching them from the air, off of leaves and flowers, out of holes left in trees by sapsuckers, and gleaning them from spider webs. Because of this, I’ve jokingly heard them called “hungrybirds.” A hummingbird deprived of food will die within hours.

Feeding hummingbirds

Ruby-throated hummingbirds live in open woodlands, meadows and grasslands, along forest edges and in parks, gardens and backyards. Feeding them is easy, inexpensive, and can provide hours of enjoyment. A sugar-water solution at a 4:1 ratio of water to white granulated sugar can provide a reliable food source. Never use anything other than white granulated sugar. Using raw sugar, brown sugar, corn syrup, molasses, honey or artificial sweeteners can cause problems. Don’t use red food coloring, either. It’s unnecessary and can harm hummingbirds, even in low concentrations. While spring water and cane sugar are preferred, tap water and beet sugar are both acceptable.

Bring the sugar-water solution to a boil, stirring until the sugar is completely dissolved, and allow it to cool. Keep in mind that bacteria and mold grow in sugar water and sugar ferments. So, fill your feeders with just enough sugar-water for two or three days of use and change it often. Extra solution may be refrigerated, but should be disposed of after a week.

Avoid locating your hummingbird feeder in direct sun, which will promote rapid sugar-solution spoilage.

Choosing feeders

Two important issues to consider in selecting hummingbird feeders are how easy they are to take apart and clean, and how large they are. The easier it is to clean a hummingbird feeder, the more likely you are to do it often and well. The best-sized feeders are those that are emptied every day or two by the hummingbirds using them.

Cleaning feeders

A dirty hummingbird feeder poses a serious risk to hungry birds. They should be taken apart and cleaned at least once a week with hot water and a bottle brush or sponge. Many hummingbird enthusiasts alternate between two sets of feeders. That way, one is always in use, while the other is allowed to soak in hot water before being scrubbed clean.