At this time of the year, I hear from a number of Missourians who want to know what has happened to the birds that seem to have disappeared from their yards or feeding stations. There is always the chance that something may have happened in their local area that caused the birds to move, but in general it’s something we expect as we transition from summer to winter.
Some of our migratory birds start leaving to head south in late summer. They may take their cues from the shortening day lengths or from the cooling temperatures. Birds that spend the winter in Missouri may change their habitat preferences for the fall and winter. American robins, common birds of lawns during spring and summer, begin forming flocks and moving to forested areas where they can hunt for invertebrates in leaf litter. Some will move south for the winter, while others remain here but aren’t commonly seen in suburban lawns. They will communally roost in thickets of cedars or other evergreen trees during cold winter nights. Similar shifts take place in other species. The cardinals that visit your feeders during the winter are often not the same individuals that you saw earlier in the year when they were nesting nearby.
Birds that move into Missouri to spend the winter may not arrive until some strong cold fronts drive them down from their more northern summer ranges. Even though today is the average day of first frost in mid-Missouri, low temperatures can fluctuate considerably in the fall. I’ve seen a couple of frosts here more than a week ago, and there is a bit of frost on a few rooftops this morning. This current lull in bird activity can persist for a while or end abruptly, depending on the weather.
Don’t worry about the current lack of birds. It's not likely to portend some approaching disaster. Save your birdseed! In a few more weeks we’ll have low temperatures near freezing, and I’m sure there will be hungry birds at your feeders.