Cardinals were once prized as pets due to their bright color and distinctive song. In the United States, this species is protected under the Migratory Bird Treaty Act of 1918, which also banned their sale as cage birds. It is illegal to take, kill, or possess northern cardinals, and violation of the law is punishable by a fine of up to US$15,000 and imprisonment of up to six months.It is also protected by the Convention for the Protection of Migratory Birds in Canada.