The flock of blackbirds raced in a tight mass above the marsh, then swirled in an impossibly tight ball, effortlessly changing directions in a matter of seconds. They looked like a single organism as they whirled, stretched out and collapsed again in a series of fluid movements in the darkening sky.
Red-winged blackbirds (Agelaius phoeniceus) are plentiful in this region. The male’s trademark red epaulets giving the species its common name.
I find it impossible to think about what the individual birds look like, though, when I’m witnessing these aerial displays. The intricate, coordinated flocking behavior demands attention to the flock as a whole, not to a single bird. Even if I wanted to, trying to track an individual bird would be impossible. There doesn’t appear to be a leader directing the complex acrobatic movements. A bird at the head of the pack is quickly absorbed in the swirling mass as it rapidly and continuously changes directions.
In the field, red-winged blackbirds look like two different species. The males are substantially larger and are all black, except for those red-and-gold shoulders. Females look like oversize sparrows, with bold brown streaking on their breasts and cryptic blacks and browns up top.
In the spring breeding period, males perch precariously atop slender grasses. From there, they sing their trademark conk-la-REE song and flash their epaulets in their “spread-song” display. Females are quieter and frequent the dense grasses below. Colors and behaviors make the males easy to identify and females easy to overlook.
Red-winged blackbirds can be found year-round in every U.S. state, large parts of Central America and the Caribbean.
During breeding season, a large number head into southern Canada to nest. They prefer marshes but will use fields with nearby freshwater if ideal habitat is unavailable. Their widespread breeding supports an enormous North American population, making red-wings one of our most abundant birds.
Insects are plentiful in marshes, of course, and they constitute the main part of the bird’s diet during the spring/summer breeding season.
The female constructs the nest low in the grass, often suspended just above the water level. She alone broods the three-egg clutch for its 12-day incubation period. Both parents feed the nestlings until they fledge two weeks later. They will continue to supply insects to begging young birds for another two weeks. Red-winged blackbirds are promiscuous. Dominant males will have multiple females in their territory, and they are aggressive about defending all of their nests. Females will readily mate with male intruders, however, so that male aggression is often ineffective. The result is most nests support chicks with more than one father.
At the end of the breeding season, red-wings switch their diets from insects to grains and fruits. They no longer need a high-protein diet to feed a growing brood. With late summer seeds plentiful, the switch is an adaptive evolutionary response to the changing environment.
In late summer, the males’ territoriality seems to switch off. Suddenly gregarious, birds of both sexes form large flocks, which often include other blackbird species as well as grackles, starlings and cowbirds. These flocks gather each evening in huge roosts that can number in the tens of thousands. In the morning, they will disperse, often miles away, to fields and marshes to feed. Come dusk, they congregate again at their favorite roosting site.
When I watch the birds exhibiting their flocking behavior, I am always amazed that they simply don’t go crashing into one another. How do they execute these complex turns in such tight formations without constantly getting in each other’s way?
Ornithologists now understand that each bird is making a series of individual decisions based on its immediate environment, not as part of a coordinated grand plan. If the bird on my right turns left, so do I. If the bird in front swoops down, so do I.
Sometimes in life I’d like to be one of those swirling blackbirds, mindlessly being swept along as part of a larger, graceful movement. I’d be happy to play a small part, and happier still to let all the responsibilities and decisions of modern life fall away and simply follow the lead of others. But then I remember that in the avian world as in our own, it’s not so simple. Winds change, obstacles appear, and suddenly a whole new set of decisions needs to be made: Lead or follow? Left or right? Faster or slower?
At home, at work, with friends, or in the anonymity of traffic, in truth we live in a complex, swirling mass of humanity, making thousands of decisions and adjustments constantly. And so, the realization comes upon me again: The goal is not to be mindlessly swept away, but rather to play a mindful role, aspiring to add a tiny element of grace to humanity’s sweep across the heavens.