Peregrine Falcons are one of the most widely-distributed species in the world, found on every continent with the exception of Antarctica. With autumn in swing, some Peregrine Falcons are migrating to their wintering areas.
There are three subspecies of Peregrine Falcons within North America. Found in the Arctic tundra is Falco peregrinus tundrius. Falco peregrinus pealei (Peale’s) is in northern Washington state through western Alaska. Lastly, Falco peregrinus anatum is found south of tundra regions to northern Mexico, with the exception of the Pacific Northwest. UT Austin’s resident falcon, Tower Girl, belongs in this subspecies.
All three subspecies have variable and widely-distributed migration patterns. Most F. p. pealei make very minimal winter migration, but some travel distances over 200 km. The Arctic subspecies, F. p. tundrius, spends summers nesting in the Arctic tundra and winters in Central and South America. These birds may fly up to 15,500 miles a year, and it’s not uncommon to see them passing through Texas. Like Peale’s peregrines, most F. p. anatum subspecies winter in their breeding range. Many falcons established in urban areas do not migrate at all, an example being Tower Girl. But as Austin is outside of the Trans-Pecos breeding area for Texas Peregrines, it’s likely she might have other reasons for sticking around other than the plentiful pigeon supply on campus. It’s possible Tower Girl might have suffered a minor injury some time ago that prevents long flights.
In Texas, fall migrating falcons can be seen as early as mid-July, and on their return to the north, migrating falcons can be seen as late as May. Typically, however, the migration months along the Central Flyway from Canada to the Texas coast are April and May for the return north, and October and November for the return south. Migrating falcons in Texas may spend several weeks here resting and feeding to prepare for the flight along the coast further south.
Some viewers watching Tower Girl in our falcon camera have expressed concern over her noticable absense from her nest box. This is normal behavior for this time of year. Tower Girl has been seen with other migrating falcons in the area. Occasionally, she stops by her nest box with another falcon resting in the vicinity.
SOURCES
Peregrine Falcon (Falco peregrinus), Migration Research Foundation (accessed online: http://www.migrationresearch.org/research/peregrine/profile.html)
Peregrine Falcon, National Geographic (accessed online: https://www.nationalgeographic.com/animals/birds/p/peregrine-falcon/)
Texas Breeding Bird Atlas: Peregrine Falcon. Texas A&M Agrilife Extension (accessed online: https://txtbba.tamu.edu/species-accounts/peregrine-falcon/)
Wild Texas: Parks, Recreation & Travel: Peregrine Falcon (Falco peregrinus) (accessed online: http://www.wildtexas.com/peregrine-falcon-falco-peregrinus/)
