About Progne chalybea (Gmelin, 1789)
The grey-breasted martin, with the scientific name Progne chalybea (Gmelin, 1789), measures 16–18 cm (6.3–7.1 in) in length and weighs 33–50 g (1.2–1.8 oz). This species has a forked tail and relatively broad wings. Adult individuals show distinct plumage differences between sexes: adult males are glossy blue-black overall, with grey-brown throats, breasts and sides that contrast against their white lower underparts. Females have duller plumage than males and paler throats, while juvenile grey-breasted martins have dull brown upperparts.
