Here are a few things I know about bluebirds: They return to our area as early as April each year, they make excellent parents and they feast on insects during spring and summer. Oh, yes, and then there's that extraordinary color, that blue beyond blue, so intense that someone seeing a bluebird for the first time invariably gasps in awe.

As recently as 30 years ago I wouldn't have written a column about these small thrushes because there was so little chance of seeing one. Sightings of bluebirds had become worrisomely rare by the 1970s but concerted action by a whole host of agencies and individuals have made them a more common sight these days (some local bluebird heroes to give thanks to: Doreen Scriven, Dick Peterson, Dave Ahlgren, Carrol Henderson and Mary Ellen Vetter).

These days, if you're near the kind of habitat they prefer — meadows and open areas with fairly short grass — you can almost count on seeing bluebirds. As a matter of fact, their preferred habitat often lies on a golf course, especially if the staff has spaced nest boxes out among the fairways. Why the preference for mowed grass? These birds are insectivores, spending much of the day perched on a utility wire or fence post, watching for juicy beetles and other ground-dwelling insects. Mowed grass makes it easier to spot a meal.

Not feeder birds

With their focus on insects, bluebirds aren't drawn to seeds in our bird feeders. The best way to entice them to stop in for a meal is to offer mealworms or grubs. Some people report success with the dried kind, but the birds seem to prefer live mealworms. Keeping insects handy can get expensive and messy, so many of us forgo bluebirds at our feeders and vow to admire them from a distance.

Food habits aside, bluebirds have fairly exacting standards for housing, too. The placement of thousands of well-constructed nest boxes around the state has been a key factor in increasing this bird's population. They use nest boxes because these approximate their traditional housing inside a cavity, formed by a woodpecker or by a branch breaking off. Since tree holes are always in short supply, nest boxes have proved to be an excellent substitute.

(In fact, I'd identified bluebirds so closely with manmade boxes that a bluebird startled me a few years ago during a casual walk through Wood Lake Nature Center in Richfield. A blue flash landed on an oak branch, then disappeared into a hole in the trunk. This most natural bluebird behavior seemed almost unnatural, after all the focus on restoring the population through the placement of nest boxes.)

Hardworking parents

A pair of bluebirds can raise two, even three broods a summer and they're some of the hardest working birds around, bringing in food and carrying out fecal sacs from dawn to dusk. As humans who monitor those nest boxes (and some golfers) can attest, they're fierce defenders of their nestlings, and will dive-bomb anyone who approaches too closely.

They are migratory, but don't travel far, most ending up in the South or Mexico for the winter. Since they're short-distance travelers, they arrive back in Minnesota before many other migratory birds. And some don't leave at all: A number of readers were astonished to see bluebirds in shrubs or at heated birdbaths this winter. As long as they can find food — mostly fruit in the winter — and water, they can survive. They're known to huddle up with others of their kind in nest boxes or tree cavities on very cold nights.

Their bigger, brassier cousin, the American robin, gets all the notice for his robust spring song, but bluebirds are fine singers, too. Their song is so soft you can easily miss it, but when your brain catches up with your ears you realize that soft warble, almost a chortle, has to mean a bluebird is nearby.

Migrant bluebirds begin to return in March, but most of them flood in during April. Keep your eyes peeled, because any day that includes a sighting of a bluebird is a good day. Their stunning, unexpected beauty has a way of cheering even the lowest of spirits.

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 val​writes@comcast.net.