Human activity responsible for billions of bird deaths annually

Human threat to billions of birds' lives

January 2011: Recent reports of thousands of dead birds falling from the sky in Arkansas represent only a tiny fraction of birds killed each year due to human causes, according to American Bird Conservancy, the nation's leading bird conservation organisation.

RISK: Wind farms such as the one at Altamont Pass in California are already killing hundreds of thousands of birds each year. Photo: Mike Parr

‘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. But because most of the deaths from those sources often occur in ones or twos, they often go unnoticed or unreported,' said ABC Vice President Mike Parr.

One billion killed flying into buildings
According to Parr, estimates from various studies show that up to one billion birds may be killed each year in collisions with buildings; another billion may die due to predation by outdoor cats; up to 50 million may die in collisions with communication towers; perhaps 15 million die annually due to pesticide poisoning and there is growing concern about bird mortality caused by the burgeoning wind industry.

‘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.

Several threats have been dramatically reduced, but much still needs to be done. For example, thanks to advocacy efforts by ABC and other members of the National Pesticide Reform Coalition, the cancellation or restriction of some of the most toxic pesticides to birds, such as carbofuran, fenthion and ethyl parathion, has reduced bird mortality by as much as 75 per cent, yet millions still die as a result of pesticide poisoning each year.

Chance to make a difference
Collisions with buildings could be drastically reduced if technology continues to advance in the development of bird-friendly or bird-safe glass for buildings. Several products have already been developed to reduce the incidence of bird impacts, but architects and city planners still need a greater understanding of the problem and the importance of making buildings bird safe.

‘Bird-safe building glass is no longer a pie-in-the-sky dream. 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,' Parr added.

Last spring, an agreement was reached between ABC and its partners and the telecommunications industry, that would dramatically reduce the number of birds killed at communication towers. If that agreement is accepted by the Federal Communications Commission, new tall towers that pose the highest threat to birds would be subject to a greater level of environmental review - including independent assessment. A preferred standard of lighting styles would also be implemented. Groundbreaking as this agreement is, it does not address the thousands of towers already permitted and built across the American landscape that continue to kill birds.

Efforts continue to reduce the number of birds killed by wind turbines. A key action that will likely be decided in the next few months will involve a decision by the Department of the Interior to implement wind turbine siting and operational guidelines. ABC believes these guidelines should be made mandatory .

‘Voluntary guidelines don't work. 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,' Parr said.