"End of Days" bird kill just a fraction of real death toll

By Morgan Erickson-Davis, mongabay.com
January 07, 2011

The sudden en-masse deaths of thousands of birds in the Southern U.S. on the night of New Year's Eve have created a frenzy of media attention, but in reality hardly compare to the massive number that die each year because of human activity.

Shortly after midnight on January 1st, thousands of red-winged blackbirds fell from the sky in Beebe, Arkansas. Some were outright dead, others mortally wounded, all were found to have suffered severe injury through blunt-force trauma. While there has been speculation around a number of hypotheses including a climate change-driven weather phenomenon and even a fluctuation in the earth's magnetism, as usual the most obvious solution is the most likely: fireworks set off by people celebrating the holiday flushed the birds into the air where, unable to see, they collided with houses, trees, and each other.

However, these deaths represent just a fraction of the true impact humans have on birdlife.

“There are many human-related causes of bird mortality including buildings, outdoor cats, pesticides, communication towers, automobiles, wind farms, and lead poisoning from spent ammunition and lost fishing tackle." said American Bird Conservancy Vice President, Mike Parr. "But because most of the deaths from those sources often occur in ones or twos, they often go unnoticed or unreported.”

Red-winged blackbirds often travel in huge flocks
In total, says Parr, studies have estimated that up to one billion birds may be killed annually due to collisions with buildings. Another billion fall prey to domestic cats. Up to 50 million birds are killed each year after hitting communications towers, and pesticide poisoning has been linked to the deaths of up to 15 million birds each year.

In addition to all these hazards, the increasing presence of wind turbines is a threat to many birds, especially when they're built in the path of migration routes.

“When you look at the totality of human-caused threats to birds, it has got to give cause for serious concern about our cumulative effects on their populations,” Parr said.

Strides have been taken in the development, implementation, and promotion of bird-safe technology. For instance, the prohibition or restriction of many pesticides most toxic to birds, such as carbofuran, fenthion, and ethyl parathion, has reduced bird mortality by as much as 75 percent.

Bird-safe glass is also being developed for use in tall buildings.

“Bird-safe building glass is no longer a pie-in-the-sky dream." said Parr. "Its reality is on the horizon – we are close. The manufacturers are working with the scientists; they’re working with us. And local communities are getting into the act as well, with more and more cities – such as San Francisco – looking at policies that implement bird-friendly construction,”

New wind technology is in the works for a turbine which would pose much less risk to birds than the design implemented in wind farms today.

Called an "airborne wind turbine", the idea is to do away with the tower of a traditional wind turbine and instead use a helium-filled blimp which would enable the device to be raised much higher than is currently possible in order to capture the increased wind energy of higher altitudes. Because its height, the device could emit a bird-deterring sound too loud for use in lower turbines.

However, while airborne wind turbines are on the horizon, today's turbines are killing hundreds of thousands of birds every year. The Department of the Interior is currently considering imposing operational guidelines on wind farms which would lessen their risk to birds. Parr believes those guidelines should be mandatory.

“Voluntary guidelines don’t work." he said. "We wouldn’t expect people to abide by voluntary drinking and driving limits. We can’t expect the wind industry to follow voluntary environmental guidelines either.”

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By Morgan Erickson-Davis, mongabay.com (January 07, 2011).

"End of Days" bird kill just a fraction of real death toll.