Can I remove Brown-headed Cowbird or other brood parasite eggs from a nest?
Brown-headed Cowbirds are native to North America, and therefore protected by the Migratory Bird Treaty Act of 1918 in the United States, and similar laws in Canada and Mexico. Tampering with their eggs or young is against these federal laws unless you hold a special permit. Keep in mind, this is the cowbird’s natural nesting strategy—they haven’t adapted to build their own nests like other birds.
Brown-headed Cowbirds are not implicated as a major cause of decline in other bird species, except for a small few such as the Kirtland’s Warbler and Black-capped Vireo. However, biologists have implemented special cowbird trapping programs in specific breeding areas to help these threatened species. Learn more about Brown-headed Cowbirds here.
Brood parasitism occurs by many species all over the world. In many cases, these birds are native where they live and breed. There are similar laws to the above in other parts of the world that have protections for native species. Contact your country’s wildlife authorities for more information.