Band-rumped Swift vs Grey-rumped Swift

Band-rumped Swift

Chaetura spinicaudus

Small16 gForest

The band-rumped swift is 10.5 to 12.6 cm (4.1 to 5.0 in) long and weighs 13.8 to 18.5 g (0.49 to 0.65 oz). It has a protruding head, a short square tail, and wings that bulge in the middle and somewhat hook at the end. The sexes are alike. Adults of the nominate subspecies have black-brown upperparts with a white band on the rump. Their underparts are dark with a slightly paler throat. Juveniles have white tips on some wing feathers. Subspecies C. s. aetherodroma is smaller than the nominate; its rump patch is grayer and its throat paler. Voice: The nominate subspecies of band-rumped swift "gives a diagnostic bisyllabic 'pseee-trr' or more burry 'prrrree-trtr'" and sometimes also "several repeated notes 'tsee-tsee-tsee'". The vocalizations of subspecies C. s. aetherodroma are not well known.

ID text from Wikipedia, CC BY-SA 4.0

Photo: Christoph Moning · CC BY 4.0

Grey-rumped Swift

Chaetura cinereiventris

Tiny14 gForest

The grey-rumped swift is about 10.5 cm (4.1 in) long and weighs about 17 g (0.60 oz). It has a protruding head, a short square tail, and wings that bulge in the middle and somewhat hook at the end. The sexes are alike. Adults of the nominate subspecies have mostly glossy black upperparts with a wide gray rump and uppertail coverts. Their underparts are a lighter gray than the rump, though darker on the undertail coverts. Juveniles are essentially the same as adults with the addition of pale fringes to many of the wing feathers. Subspecies C. c. Voice: The principal vocalizations of the grey-rumped swift's nominate subspecies are "a bright repeated short 'tsip'" and a "series of 3–4 slightly downslurred burry drawn-out notes 'trrreeew-trrreeew-trrreeew'." The other subspecies' vocalizations vary but are similar to them.

ID text from Wikipedia, CC BY-SA 4.0

Recorded by Niels Krabbe · Call · Pichincha: Río Guaycuyacu, Ecuador · CC BY-SA 4.0

Photo: er-birds · CC BY 4.0

Photos and recordings are credited to their authors under the licence shown. Full profiles: Band-rumped Swift and Grey-rumped Swift.