Why do birds huddle on power wires?
The response was sarcastic?It's easier to sit in a circle.Or maybe "Because they can."
Even though there are plenty of tree branches and other natural perches to be had, what really attracts birds to human strung wires?Birds land on power lines to warm their feet in cold weather, according to one of my childhood camp counselors.I suspected he was just winging it because birds land on electrical wires in warmer weather.So, really?
Mark LaBarr is a wildlife biologist and program manager with Audubon Vermont, a program of the National Audubon Society.The bird-banding station at the Green Mountain Audubon Center is run by LaBarr, who has been with the nonprofit for 19 years.There are more than 200 bird species that breed in Vermont.
There are various reasons for perching on utility lines.The lines give falcons a bird's-eye view of their prey.Birds that catch their food on the wing hang out on power lines to see juicy meals as they fly by.The wires have no foliage to block the view or hide the predator.
In the late summer and early fall, some bird species cluster on wires in what LaBarr describes as a "pre-migratory get-together."The wire is used as a staging area before the flock takes flight for warmer climates.
Birds on a wire aren't a year-round phenomenon, even for species that stick around for the winter.He says we won't see birds lined up during the breeding season because it's not good for them to have competitors crowding their space.Birds are more likely to flock together after the breeding season is over.
As it often appears, birds step aside to make room for a new bird.
"I'm sure there's some shoving going on there," LaBarr says."But whether a bird actually says to itself, 'Oh, I'll move over and allow some other bird to join us here on the line,' I don't think they consciously do that."There's safety in numbers with flocking behavior.Their chance of being hit by a predator is reduced by 50 percent if they have one more bird sitting next to them.
Birds on a wire always face in the same direction.
I'm sure there's the odd bird that faces the opposite way, but I guess they do, come to think of it.They're not like us.
There are a couple of possible explanations for the alignment.It's easy to take off and land facing into the wind.Birds don't get ruffled when facing the weather.
The reason birds don't get electrocuted when they cling to high-voltage wires is because of basic physics.
It doesn't mean that birds never get killed by power lines.Birds with larger wingspans are more likely to build a nest on utility poles.They get fried when they touch two wires at the same time.Nested platforms are built by utility companies to prevent deaths and disruptions to the electrical grid.
LaBarr says that electrocution pales in comparison to other human-created threats, such as habitat destruction, windows and even domestic cats.According to a study conducted by the University of Georgia, free-ranging felines kill an estimated 4 billion animals annually in the U.S., including 500 million birds.