Why did bald eagle populations decline in North America during the twentieth century?

Bald eagle populations declined in North America during the twentieth century due to human activities. These included hunting for sport and bounties, as well as the widespread agricultural use of the pesticide DDT after World War II. DDT accumulated in the birds' tissues, causing eggshell thinning and making the shells easily breakable, which led to fewer young being produced. Habitat loss due to human population growth and urban development also contributed to the decline. The use of DDT was banned in the United States in 1972, and conservation efforts, including criminalizing the hunting of bald eagles, helped their populations recover.123