Costa's Hummingbird vs Calliope Hummingbird

Costa's Hummingbird and Calliope Hummingbird can be distinguished by their structural features and plumage. Costa's has a shorter bill and more compact body, while Calliope is slightly larger with a longer bill. Plumage differences are subtle but include distinct gorget patterns in males.

1. Bill Length: Costa's has a shorter bill; Calliope's is longer. 2. Male Gorget: Costa's displays a flaring purple gorget; Calliope's is streaked magenta. 3. Structure: Costa's is more compact; Calliope is slightly larger.

Costa's Hummingbird is more compact with a shorter bill compared to the slightly larger Calliope Hummingbird, which has a longer bill.

Male Costa's Hummingbird has a vibrant purple gorget that flares out, while the male Calliope Hummingbird has a streaked magenta gorget. Females and immatures of both species are more challenging to distinguish.