The concept of subspecies is an important tool to help categorize and conserve biodiversity; thus, delineating the range of subspecies can have important management and conservation implications. The Peregrine Falcon (Falco peregrinus) is a widespread species that occurs throughout North America, where three subspecies are recognized: F. p. anatum, F. p. pealei, and F. p. tundrius. In Alaska, all three subspecies breed and their general distributions during the breeding season are well documented. However, the limits of their distributions were unclear or unconfirmed, especially those of F. p. anatum and F. p. pealei along the Lost Coast in the northeastern Gulf of Alaska. We describe plumage, morphology, and/or movements of Peregrine Falcons known to have nested (n = 6) or hatched (n = 3) within the Lost Coast and used this information to determine their subspecific group. For all nine birds, we found these characteristics to be consistent with F. p. anatum. Our results underscore the importance of delineating geographic range and distribution of subspecies prior to environmental catastrophes and to ensure reliable interpretation of species status and trends. We believe this type of life-history and demographic information will become even more valuable as the effects of a changing climate are realized.