- Hunting & Shooting: In the 18th and 19th centuries, bald eagles were often seen as a threat to livestock and agriculture, and were routinely shot and killed.
- Pesticide Use: The widespread use of the pesticide DDT had a devastating impact on bald eagle populations. DDT caused eggshells to become thin and easily break, leading to a decline in reproduction and a decrease in the bald eagle population.
- Habitat loss and Destruction: The destruction and alteration of their natural habitats due to human activities such as logging, urbanization, and agriculture also contributed to the decline.
Due to these factors, the bald eagle population declined drastically, and the species was classified as endangered in the 1970s.