Alpine Swift vs Pacific Swift

The Alpine Swift is larger and more robust than the Pacific Swift, with a distinctive white belly that contrasts sharply with its darker upperparts. The Pacific Swift is smaller, with a more uniformly dark plumage and a slightly forked tail.

Look for the Alpine Swift's larger size and distinctive white belly when in flight. The Pacific Swift's smaller size and uniformly dark plumage can help differentiate it from the Alpine Swift.

The Alpine Swift is noticeably larger and more robust compared to the smaller and more slender Pacific Swift.

The Alpine Swift has a prominent white belly and throat, which contrasts with its dark brown upperparts. In contrast, the Pacific Swift has a more uniform dark plumage with a less distinct white throat patch.