The same towers that beam images of aviary wildlife into our homes are killing them by the millions, says a new study published Wednesday by researchers at Environment Canada and at U.S. agencies and universities.
As Postmedia News reports, wildlife authorizes claim that nearly seven million birds are killed every year as North American communications towers keep growing taller and taller. And the worst part, says the study's lead author, is that it's completely avoidable.
"This tragedy, it doesn't have to be," Travis Longcore, of the University of Southern California, told the news network.
In fact, small changes, such as adjusting the tower lighting from a solid red beam to a series of blinking lights, could effectively shave the death toll in half. As the study, published in PLoS One journal explains, the birds become hypnotized by the unwavering red lights that are designed to keep planes at a safe distance. When the weather gets ugly, migrating birds tend to fly at lower altitudes and the clouds make it hard for them to use traditional navigation tools such as stars.
The towers' lights are irresistible to the birds. Unable to tear themselves away, our feathered friends start flying laps around the structures until many of them die of exhaustion or get trapped in the guy wires. Surprisingly, the risk of death from smashing into the towers figures relatively low on the scale.
Over the past three decades, research shows the amount of deaths has exploded. In 1979, one million birds met their untimely end via tower. Now, the 84,000 communications towers spread out over Canada and the U.S. are responsible for 6.8 million bird deaths each year. Cell phone towers, on the other hand, stand relatively low and do not pose as large a threat.
Longcore also warns that most of the bird casualties happen to be culled from the songbird populations that are heading up to Canada from their winter migration spots in Central and South America.
"Many of the birds are of conservation concern," he added.
Now for the solution part. The study estimates that by changing the solid red light to a blinking light on the 4,500 towers that measure over 150 metres, more than 2.5 million birdie lives would be saved per annum, plus pilots would still be able to see the structures.
Another suggestion is for companies to start sharing towers to reduce their numbers and if they have to build new ones, to opt for free-standing towers so that fewer guy wires run the risk of behaving as inadvertent bird snares.
Pierre Mineau of Environment Canada's National Wildlife Research Centre co-authored the study.