Mourning doves sound just like they look — soft, shy, gentle. Hard to imagine the caw of a crow coming from a bird that looks like a dove.

Doves do not have an extensive vocal repertoire; coo sums it up. Unmated males sing what ornithologists call an advertising call — a long soft coo followed by two or three louder coos. This is repeated and repeated (and repeated) from a perch, beginning shortly before sunrise and again at dusk.

That's the call I remember hearing as a kid in Robbinsdale. Evening, quiet neighborhood, doves calling from power lines above our street.

Mourning doves are thought by some researchers to be the most common native bird in North America (replacing the passenger pigeon, both members of the same family). Estimates vary widely, though, from 175 million to 450 million. Red-winged blackbirds would be second, or first, depending on who does the estimating.

The doves are found throughout the continent, a stable population in the East, declining in the West.

Bob Janssen in his new book "Birds in Minnesota" says the species is declining here. That's determined by annual counts for what is known as the breeding bird survey, a statewide census by volunteers.

Mourning doves migrate, their spring return peaking in early May.

They also overwinter, adding variety to bird feeders. They are common in the metro area in winter.

The bird has been documented as nesting in 82 of our 87 counties.

The Eurasian collared-dove also is listed as regular here, most often seen in towns with grain elevators. It shares a grain diet with the mourning dove. The collared dove is larger, lighter in color, with a distinctive black collar.

In the early 19th century the collared-dove was confined to subtropical Asia. The population had spread to England by 1953. Dispersal is its nature.

In 1974 a few dozen escaped captivity in the Bahamas. The birds soon found Florida, spreading then throughout North America. They first nested in Minnesota in 2001.

We have been visited in very small numbers by three other North American doves — Inca dove, common ground-dove, and white-winged dove. There are 11 dove species in North America, those mentioned plus Key West quail-dove, ringed turtle dove, rock dove (aka common pigeon), ruddy ground dove, and spotted and white-tipped doves.

Depending on weather, mourning doves can nest as often as six times a year. They lay two eggs each time. In Minnesota, nesting twice a year is probable.

The birds nest in dense shrubs or evergreens, building flimsy constructions of sticks and twigs. I've seen one such nest, and flimsy was a complimentary term. You can build nesting platforms for doves, simple hardware-cloth cones that might attract the birds to your yard. See nestwatch.org.

Doves are ground feeders. Toss millet, cracked corn or other grain on the ground or offer it on a platform feeder.

Mourning doves are the most common game bird in the U.S., a recent fall population estimated at 350 million. Hunting is said to harvest about 15% of that number.

Minnesota reinstated a dove hunting season in 2004 after a 57-year hiatus. The daily possession limit here is 15 birds. They are not widely hunted. It takes several birds to make a meal.

Mourning doves on average live 18 months, hunted or not. Weather, predation and accidents temper the population.

Lifelong birder Jim Williams can be reached at woodduck38@gmail.com. Join his conversation about birds at startribune.com/wingnut.