When you think of pollution, what image comes to mind? Litter? Oil spills? We think of these types of pollution first because they are visible. But the most dangerous form is one that we cannot see: air pollution.
We know that chemicals and small particles in the air can harm human health, so governments create laws and programs to reduce air pollution. We wanted to know if these same programs also positively affect birds. After all, birds are such an important part of our world! We built a mathematical model using bird population and air pollution data to see which air pollutants (tropospheric ozone and/or fine particulate matter) harm birds. Then we looked at how a United States air pollution reduction program affected the bird populations. From this analysis, we found that air pollution programs not only benefit humans, but they also protect birds.