Usually, by this time, we hear the first hollow, mournful cooing of the mourning dove. Such wintering over birds always are heard cooing by the first week in March, heralding spring. It's the male mourning doves that produce the distinctive four-part song -- "coah, cooo, cooo, cooo." At a distance, only the three coos may be audible.

Thirty five years ago, a wintering mourning dove was a fairly rare sight in the Twin Cities. Now they are quite common at feeding stations in southern Minnesota throughout the frozen season. However, most still head for the southern U.S. in autumn. Reports from avid birders confirm that the mourning dove's winter range is moving north. Our warmer winters and proliferating feeding stations probably account for the extended range.

Pairs of mourning doves are commonly seen in the summer on utility wires or picking up gravel along roadsides. These birds are a foot long, have small heads and long pointed tails. They are gray and brown, and their tails are bordered with large white spots. The whistling of their wings is distinctive.

JIM GILBERT