Something small and quick flashes through the backyard and suddenly you realize that a hummingbird, the first of the season, has just zipped by.

Spring is an exciting time of year for hummingbird fans as these smallest of birds return from their winter homes in Central America. Everyone exults at the sight of vibrant little birds with such an acrobatic flight style and the male's chip-on-the-shoulder personality.

In fact, everything about hummingbirds, from their diminutive size (3¾ inches for ruby-throats) to their superfast wing beats (60 to 80 per second, so fast their wings almost disappear in a silvery wash), is larger than life. It's tough to find enough superlatives to describe these most unbirdlike of birds, with a diet largely made up of flower nectar and a unique wing arrangement. This allows them to not only fly backward but also accomplish the difficult and energy-consuming task of hovering, either at a flower face or some other object that intrigues them.

The western U.S. hosts as many as eight different kinds of hummingbirds, but in the eastern half of the country we see only one, the ruby-throated. This can be confusing, because only the males display that brilliant-in-the-sunlight red throat — females are much duller but do have lovely iridescent green backs.

During spring's migratory period, throughout the month of May, a number of hummingbirds may stop at your nectar feeders for a quick energy drink.

But the big question on everyone's mind is: Will those hummingbirds stay around for the summer? And the answer is, it depends. Males are in the vanguard, arriving in early May and eager to claim a feeding territory right away. Females arrive a couple of weeks later, and know to avoid the feisty males, except briefly at breeding time. These birds don't form pair bonds, and the female is on her own to build a nest, incubate her two eggs and raise the nestlings.

If a male has adopted your home landscape as part of his feeding territory, then you may be rewarded by daily visits to gardens and feeders. Females tend to avoid a male's territory (these are defended viciously), preferring to nest in a secluded wetland, but these are in short supply in the Twin Cities. So it's not unusual for a female to nest in a residential area, if it has the right habitat.

Habitat is the key, and as is true for most birds, native plantings play a big role. Yes, it's true that as far as collecting nectar is concerned, hummingbirds aren't picky and will poke their long beaks into just about any kind of bloom in search of the sweet stuff. But they need protein, too, and this is supplied in the form of small arthropods like spiders, gnats, fruit flies and tiny caterpillars. Native plants are attractive to native insects — and nonnatives don't attract many insects at all. Thus, landscapes that are magnets for hummingbirds might feature some bright nonnative annuals like lantana and salvias, but also natives like bergamot, columbine and cardinal flower.

Where did my hummingbirds go? This is a frequent lament after May's heady rush of little birds. The males may be feeding elsewhere and even if a female is in the vicinity, she sits on her nest almost around the clock, dashing off for 2 minutes each hour to feed herself. Once the eggs hatch, she's intent on bringing back insect protein to help her nestlings grow quickly, and makes few trips to nectar feeders. So summer may not be the best hummingbird viewing time for most of us.

But late summer and fall can be ideal times to see backyard hummingbirds: Adults are moving through as they begin to head back to Mexico and Central America, and their population is boosted by summer's crop of youngsters. August and September are when hummingbirds often stack up at feeders, seeking energy to fuel their long migratory trips.

St. Paul resident Val Cunningham, who volunteers with the St. Paul Audubon Society and writes about nature for local, regional and national newspapers and magazines, can be reached at valwrites@comcast.net.