How Does Acid Rain Affect Animals?
Acid rain severely impacts animals, particularly aquatic life, by altering the chemical composition of their habitats. The increased acidity in water bodies leads to a decline in fish and other aquatic animal populations.
The most visible effects of acid rain are seen in aquatic ecosystems. As the acidity of lakes, streams, and marshes increases (lower pH), the water becomes clearer, and the number of fish and other aquatic animals decreases significantly. This is because acid rain:
- Directly harms aquatic life: Many aquatic organisms, such as fish and arthropods, cannot survive in water with a pH below 5. The acidity directly damages their gills and other vital organs.
- Leachs aluminum from soil: Acid rain flowing through the soil dissolves aluminum, which then enters waterways. Aluminum is toxic to fish and other aquatic organisms. The EPA highlights this process in their reporting. https://www.epa.gov/acidrain/effects-acid-rain
- Disrupts the food web: The loss of sensitive species disrupts the entire food web, impacting the populations of other organisms dependent on them. This is detailed on the EPA's student website focusing on food webs. https://www3.epa.gov/acidrain/education/site_students/foodweb.html
Terrestrial Impacts
While less directly obvious, acid rain also affects terrestrial animals:
- Soil acidification: Acid rain acidifies soil, reducing nutrient availability and potentially harming soil organisms. This, in turn, can impact the food sources for many animals.
- Indirect effects: The decline of plant life due to acid rain can reduce food and shelter for many animals.
- Increased toxicity: Acid rain can increase the concentration of toxic metals in the soil, which can be ingested by animals, leading to health problems.
Several sources, including the Alberta government, have documented the chronic impact of acid rain on lakes and streams. https://landuse.alberta.ca/Forms%20and%20Applications/RFR_ACFN%20Reply%20to%20Crown%20Submission%205%20-%20TabD9%20AcidRain_2014-08_PUBLIC.pdf The Canadian government also notes that acid rain changes water quality, making it unsuitable for some animals. https://www.canada.ca/en/environment-climate-change/services/air-pollution/quality-environment-economy/ecosystem/wild-animals.html
