Black Rosy-Finch Overview, All About Birds, Cornell Lab of Ornithology

The breeding biology of the Black Rosy-Finch is unusual in that a male primarily defends a floating territory around his mate, rather than a fixed piece of real estate. As a result, males constantly chase other males that approach their mates too closely, and females are most readily located by looking near the center of all the fighting.

Wintering flocks of Black Rosy-Finches roost in large communal roosts in caves, mine shafts, on rafters of barns, and in clusters of old Cliff Swallow nests.

Black Rosy-Finches are among the least studied of North American birds because of the inaccessibility of their alpine habitat generally and their nest sites on cliffs in particular. Reflecting this, actual nests had been reached by only three researchers as of 2002.

The oldest recorded Black Rosy-Finch was a male, over 8 years, 7 months old when it was recaptured and rereleased during banding operations in Wyoming.