The Eurasian Collared Dove was introduced from Europe and has rapidly colonized North America. The first record of the species in Montana dates to 1997, but they are now widespread (Montana Bird Distribution Committee 2013). They may initially be confused with our native Mourning Dove, but are larger and heavier, have a broad square tail, and have a black collar on the back of their neck.
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.