Drongo de Ludwig vs Hirondelle à croupion gris

The Square-tailed Drongo and Grey-rumped Swallow are easily distinguished by their tail shapes and plumage. The drongo has a square tail and a more greenish or bronzy appearance, while the swallow has a grey rump and a streamlined body suited for flight.

Tail shape is the most reliable field mark: the drongo has a square tail, while the swallow's tail is more streamlined. Plumage differences include the drongo's greenish or bronzy sheen compared to the swallow's grey rump.

The Square-tailed Drongo is less glossy with a more greenish or bronzy sheen, whereas the Grey-rumped Swallow has a distinctive grey rump.