Behavior

Away from nesting grounds generally occurs in groups, which appear to be more vocal than White-collared Swift (Streptoprocne zonaris), and engage more in diving and joint maneuvers. At breeding grounds, occurs in colonies of up to 200 individuals. Observed together with Chestnut-collared Swift (Streptoprocne rutila) and the little known White-fronted Swift (Cypseloides storeri) near a nesting colony at a waterfall near Tacambaro, Michoacan. Observed in group flight over a mountain ridge near Omiltemi, Guerrero with Vaux's Swift (Chaetura vauxi) and Black Swift (Cypseloides niger). Birds make daily movements away from breeding grounds of at least several kilometers.

Occurs in large breeding colonies of up to 200 individuals per cave, so apparently little individual territoriality.

No information. Diving flight may be part of display, like it is thought to be in White-collared Swifts.

Birds often fly in unison within a flock, and may be more social than White-collared Swift (Streptoprocne zonaris). Observed flocking with several other species of swift, including Black (Cypseloides niger), White-fronted (C. storeri), Vaux's (Chaetura vauxi), and Chestnut-collared (Streptoprocne rutila) swifts (Howell et al. 1997, personal observation).

Near the Dos Bocas cave in Parque Nacional las Grutas de Cacahuamilpa near Cacahuamilpa, Guerrero, Peregrine Falcons (Falco peregrinus) were observed just outside the cave opening waiting to catch swifts (Rowley and Orr 1962).

The lice Dennyus semicollaris was described from White-naped Swift speciments (Price and Beer 1962). Additionally, the tick Ixodes cuernavacensis was described from White-naped Swifts (Kohls and Clifford 1966).