A blur of iridescent green feathers buzzes through the humid fall air.
Weighing little over a tenth of an ounce and traveling at up to 60 mph, the ruby-throated hummingbird, one of millions that pass along Texas’ gulf coast during their late-summer migration south, is hardly noticeable.
That is, unless you’re Adriana Cooke. Her office’s north-facing window in downtown Victoria’s Prosperity Bank was bombarded by them daily for more than two months, she said.
On any late summer day, outside her window lay three to four hummingbirds in various degrees of carnage.
It’s a fate that awaits about one billion birds each year.
“Birds, with their pea-sized brains, see the reflection of the sky, clouds and trees in the glass which all appear to be ‘real’ so they keep flying until they strike the glass which usually causes death or severe internal injury,” said Clifford Shackelford, statewide non-game ornithologist for the Texas Parks and Wildlife Department, in an email.
The Prosperity Bank building, with its large wall of black, shiny windows, looks to birds like a continuation of the sky.
“That looks like highly reflective glass – almost like mirrors – that was commonly used in 1970s and 1980s construction,” Shackelford said in reference to a photo of the building. “Notice how reflective it is – I can see the trees and next door building.”
The north-facing direction spells trouble for southbound birds, although Shackelford said any window can be hazardous.
Cooke said she’d also heard of birds hitting the windows of Vela Farms On The Square, also located on DeLeon Plaza.
Although most of the bigger birds she’s seen hit the windows will get back up and shake it off, Cooke said the hummingbirds often can’t handle the impact.
According to Shackelford, injury depends on the bird’s speed and momentum when it hits the glass.
From a standing start, hummingbirds can rev up speed to 60 mph in a distance of three feet and have a higher energy output per unit of body weight than any animal in the world, according to the Texas Department of Wildlife.
The death caused by impact isn’t a pleasant one, or necessarily quick.
“Death, sadly, comes hours later after a lot of pain and suffering,” Shackelford said. “To be able to fly, birds’ bones are hollow so they can snap like toothpicks.”
To prevent window collisions, All About Birds, an online resource made available by The Cornell Lab, recommends marking windows with tempera paint, soap, decals or bird tape, or installing Acopian Bird Savers, screens, netting, or one-way transparent film.