Unfortunately they sometimes eat grain, which has the opposite effect. They feed on insect pests such as corn earworms, as well as on weed seeds, facts which should endear them to us. Lawrence Valley as they are in the upper Midwest.Īll blackbirds, red-wings included, are omnivores. And admittedly they aren’t as numerous in the St. But blackbirds are smaller and migrate primarily at night, plus they don’t have the pipes that geese have, and their voices don’t carry as far. Even if their chevron-shaped flocks don’t catch your eye, their loud honking will let you know what’s up, so to speak. Dolbeer of the USDA-APHIS Wildlife Services in Denver says that a single flock may contain over a million blackbirds.Ĭanada geese migration is hard to miss. After all, their flocks are much larger, in terms of numbers, than those of geese. Lawrence Valley.Ĭonsidering that red-winged blackbirds are the most numerous bird species in North America, it seems odd that their migration often escapes our notice. Although grackles, cowbirds and the invasive starlings are lumped into the category of blackbird, it’s our native red-winged blackbird ( Agelaius phoeniceus) that I most often see in the St. With all due respect to migratory geese (and to those tasked with maintaining order amid groups of youngsters), watching a flock of tens of thousands of blackbirds turn, wheel and dive in unison is far more captivating. Teachers, daycare workers, and other sorts of cat-herders are no doubt impressed that Canada geese manage to organize V-shaped follow-the-leader flight formations without any noticeable squabbling. “I was watching the ones that were still on the ground and hoping they would get up and fly,” Edwards said.Autumn heralds its arrival with all manner of colorful cues: Tree leaves explode into brilliance gray squirrels feverishly hoard food supplies yellow school buses come out of hibernation, and most remarkably, blackbird flocks practice their aerial gymnastic routines. The bird-loving scientists hope the survivors make it to where they were headed without further incident. (There’s also the fact that toxic fumes would have affected other wildlife in the area.) As for 5G interference, Edwards and Termignoni Garcia shook their heads. If they had inhaled poisonous gases or been shocked, the physics of their movement would have been entirely different. First, it’s clear in the video that they weren’t disoriented but were flying extremely fast. The researchers were skeptical of the many internet theories about the birds of Cuauhtémoc. “These phenomena are caused by the constant process of urbanization and they will be more frequent as our cities grow,” said Termignoni Garcia. Last year, hundreds of songbirds crashed into skyscrapers in New York. Migratory birds are known to make fatal mistakes, often involving reflective glass. By the time they realized they were wrong, there was no turning back. From above, these roofs reflect light the same way a body of water does, so the birds might have been looking for a quick drink. Termignoni Garcia focused on the laminated roofs of the houses. The point is, most of the birds would follow rather than be aware of where they actually were in 3D space.” Maybe some sort of stochastic event caused the leader of the flock to dodge something - maybe it was dodging the wires or maybe it just made a mistake. “If that’s the case, then most of the birds in the flock wouldn’t know they’re close to the ground. “Maybe the leader of the flock somehow didn’t know they were close to the ground,” Edwards said. and Canada but winter in Mexico, have ben known to travel in groups of 3,000, so it’s easy to see how one mistake could lead many to their doom. Yellow-headed blackbirds, which live primarily in the northern U.S. “They’re not looking very distant they’re actually following their closest neighbor in the flock so basically taking cues on where to move based on their closest neighbor,” Edwards said. One bird sets the pace and direction, the others just go along with what everyone else is doing. They say that when migratory birds fly in large flocks, they follow the leader. Edwards, Alexander Agassiz Professor of Organismal and Evolutionary Biology, and Flavia Termignoni Garcia, a postdoctoral researcher from his lab who studies bird behavior, believe the truth lies in flock dynamics.
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