In winter, it’s common to see mixed-species foraging flocks moving swiftly through the landscape. These flocks are composed of birds of different species that feed together. Common members of mixed-species flocks include nuthatches, titmice, chickadees, juncos and other sparrows, kinglets, and downy and hairy woodpeckers (side note: there are a lot of woodpeckers around this winter). You’ll find numerous theories about why birds form these flocks: as with any flock or herd, there’s safety in numbers; also, because they’re all looking for different foods in slightly different ecological niches, they don’t compete, and they help each other forage.
Birds are quite specific when they forage: some are ground feeders, some feed on branches, etc. So in a mixed-species flock, some birds will be searching the standing perennial stalks for remaining seeds while others forage on the ground for fallen seeds and insects. Each species may lead the others to sources of food, but they don’t compete. An ecological garden with many species of native plants, including grasses, perennials, and shrubs, is the perfect habitat for these flocks. From the birds’ point of view, this type of habitat is greatly preferable to artificial food sources like feeders.