Effects of air pollution on birds

Our project aims to find out what kind of effects air pollution has on free-living bird populations. Besides accumulation of toxic compound in birds we are especially interested in physiological and ecological effects. A motivation to our work has been the observation that despite ample information on concentrations of pollutants in nature, little is known of the actual effects of the pollutants in wild, including their secondary effects in a food chain.

Pollution-related nutritional changes, that are complex in wild populations, cannot be evaluated in laboratory, which means that a species living in its natural environment may be in hazard even though laboratory experiments fail to show any impact. One of the main issues in our study is the different ability of bird species to tolerate environmental stress such as pollution, and how this ability is connected to their diet. At the moment we are especially interested in some important dietary components, calcium, carotenoids and vitamins, all of which may be affected by air pollution.

Our main study area is the surroundings of a Finnish copper smelter. This area is well suited for our study because of a strong pollution gradient and ample background information on the effects of pollution on wild bird populations, due to the earlier work of our research group. Elevated heavy metal concentrations (e.g. Cu, Ni, Pb and As) occur in soil, vegetation, insects and birds in the surroundings of the factory due to long-term deposition. We have put up about 600 nest-boxes for birds along the pollution gradient and information on birds breeding in this area is available from the beginning of the 1990’s.

Tapio Eeva