When you think of the sights and sounds of fall in North Dakota, flocks of snow geese and other waterfowl overhead come to mind, as do the leaves changing color. But one thing that's many of us overlook (with the exception of farmers) are the large flocks of red-winged blackbirds that swoop and swirl over sunflower fields and other areas.
Those large, dense flocks of birds have puzzled humans for millennia. But, more recently, scientists have come to better understand the phenomenon.
These murmurations, a term derived from the low “murmuring” resulting from the sound of their wings and soft calls. They have been described as a display of teamwork, athleticism, and artistry. Not all birds form murmurations. Starlings are often cited as forming them. So are red-winged blackbirds, grackles, some shorebirds, swallows, and snow geese.
The rules of the game for birds in a murmuration are don’t fly too close together, don’t fly to far apart, and fly in the same direction as the others. There is no leader in these flocks. Rather, each bird instantly reacts to the movements of a half dozen or so of its closest neighbors. So, the entire flock can rise or dive, expand or contract, swoop and turn, as though it were one big organism.
Murmurations are more frequent during the fall and early winter when the birds are moving in large flocks. Birds do not form murmurations during the summer months. They are too busy mating, nesting, and rearing their young. But come fall and early winter some species form these large flocks particularly during late afternoons and evenings before they roost for the night.
Why do some birds form a murmuration? One commonly cited hypothesis is that it may be a defense mechanism to confuse predators (e.g., falcons). Hunters can relate to that when it comes to a large flock of snow geese, covey of qual, and the like. Most young hunters learn early on not to “flock shoot.” You are likely to come up empty. Chances are much better if you pick out a bird in the flock to shoot.” Others suggest that the phenomenon may be related to finding a good feeding area or to help them stay safe and warm when making their way to a communal roost.
