posted January 15th, 2010; last edited January 15th, 2010 –– David Sibley
2 comments to Bird_mortality_chart
Wow, I didn’t realize the magnitude of cats and windows vs. other causes for bird mortality. One item I hear about in my area (Pacific Northwest) is wind turbines, and I often wonder about pesticide use. Thanks for the info!
Hi Kersten, Yes – cats and windows have by far the biggest impact, at least based on these estimates (which come from various sources). Wind Turbines are certainly a hot topic these days, and as the number of wind farms grows the potential for significant bird mortality has to be considered. The infamous Altamont Pass wind farm killed relatively small numbers of birds but a shocking number of Golden Eagles. A lot has been learned since then, and modern wind farms should be a lot safer. I generally support wind energy development, and think the potential damages have to be weighed against the known damages of fossil fuel production (oil, gas, and coal) which probably kills and/or displaces millions of birds around the world each year. And if we were more efficient about our energy use then wind and solar and other sustainable energy could provide all of our needs.
Pesticides and other persistent chemical pollutants are a very real problem, but there is no way to quantify the impact on birds. Many chemicals affect a bird’s behavior or reproduction, having sublethal impacts that take that individual out of the breeding population and effectively reduce the population.
So go organic and go efficient!