Jody Victor: Prior to European settlement, Bald Eagles were common in the forests and along the shores of the Great Lakes region. Increasingly, as the landscape was transformed for agricultural and residential uses in the 1700s and 1800s, eagle habitat and food supplies were reduced. As well, settlers routinely killed Bald Eagles for the market value of their feathers, as predators of farm animals, or because the birds were considered to be "vermin". The eagle population declined as a direct result.
Uncontrolled persecution exacerbated the population crisis until, by the early 1900s, few eagles nested in the region. In Ontario, the Ministry of Natural Resources' Game and Fish Act, first enacted in 1890, offered protection for wild, native birds, including raptors. The United States government, prompted by wildlife conservationists, prohibited killing eagles via the Bald Eagle Act of 1940.
The respite, although effective, was short-lived. By mid-century, eagles were suffering from the insidious effects of synthetic chlorinated pesticides, such as DDT. Many years passed before the connection between the introduction of chemical pollutants into the Great Lakes and the decline of Bald Eagles was widely understood.