Rusty Blackbird populations have been declining precipitously throughout their range, and the causes of these disturbing trends are not yet entirely understood. Rusties feed singly or in mixed flocks during the winter in the southern U.S., often occurring with other species that are considered pests. The Migratory Bird Act allows take of blackbirds, cowbirds, grackles, crows, and magpies when individuals are “found committing or about to commit depredations upon ornamental or shade trees, agricultural crops, livestock, or wildlife, or when concentrated in such numbers and manner as to constitute a health hazard or other nuisance.” Although Rusty Blackbirds do not appear to have an impact on crops, they can become victims of control efforts aimed at other species, particularly at night roosts. The impact of control efforts on Rusty Blackbird populations are unknown.
In response to Rusty population declines, the U.S. Fish and Wildlife Service recently removed Rusty Blackbirds from the list of species for which take is allowed "because of long-term evidence of population declines throughout much of their range." A depredation permit is now required to conduct control actions affecting the species. Also, nontoxic shot or bullets must be used in most cases when a firearm is used to control the species. Finally, any control actions must be reported.
The Mexican (Tamaulipas) Crow was also removed form the list due to declining populations.
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