The Chimney Swift is an agile insectivore popularly described as “a cigar with wings”. These birds nest in hollow trees, abandoned buildings, silos, barns, and, true to their name, chimneys. This means these birds can be observed foraging high above cities and suburbs as well as above forests, open areas, as well as lakes and ponds. Birds will frequently forage and roost together in large flocks. Birds give a high-pitched, buzzy chip call referred to as a “chipper call”. These birds are frequently seen out foraging at dusk before heading to their nesting or roost sites. Pairs select nest sites which are dark and well-sheltered. Both males and females gather twigs which are cemented together using their saliva to form the nest which is attached to a vertical wall. Both birds incubate their eggs and rarely ever leave them unguarded. Both parents feed and brood their young and may be assisted by additional adult helpers. After about 2 weeks, the young will leave the nest and cling to the wall with their nest mates. In the first week of flights, family groups will return to the area near the nest site and roost together. Family groups break up or depart for communal roosts soon after these first flights.
Safe Dates: May 20th to August 1st (applicable for only the S or H codes).
Breeding Evidence: If you hear the buzzy calls of Chimney Swift within the safe dates, use code S. The simplest way to upgrade this to a “Probable Breeder” is to listen for singing again at the same location 7 or more days later to upgrade the code to S7. For silently foraging Chimney Swift, use code H. If you observe a bird visiting a potential nest site such as a chimney, hollow tree, or other suitable site, use code N. Chimney Swift are one of the few birds which copulate while in flight (code C). Adults gather materials for nest building by breaking off twigs from tree tops (code CN).