The Common Ternís long and attractive tail streamers were once coveted adornments for ladiesí hats; as a result, these birds were hunted vigorously in the late 19th century and extirpated from much of their North American range. With the passage of bird protection legislation, however, populations quickly recovered and by the 1930s the Common Tern had made a comeback.
However, the species declined again later in the 20th century, reflecting loss of habitat, toxic contamination of water and food sources, and increased human disturbance of nesting areas. Numbers in the Great Lakes region have dropped about 70 percent since 1960. Efforts to restore tern populations and habitat have included the creation of protected, human-made islands for nesting.