Costa’s hummingbirds are the second-smallest North American hummingbird species. They measure 2.8 – 3.5″ (7 – 9 cm) in length (from bill to tail). They weigh between 0.09 – 0.12 oz (2.5 to 3.5 g) – the average male weighs 0.10 oz or 3.05 g and the average female weighs 0.11 oz or 3.22 g.
Common Physical Traits:
- The upper plumage of both the male and female is an iridescent green.
- The dull black bill is long, straight and thin.
- The eyes are dark brown to black.
- The legs and feet are dark brown to black.
- The plumage below is whitish with greenish flanks.
Adult Males
- The male’s most distinguishing feature is his iridescent violet / purple cap and gorget (throat patch). In poor light conditions, the crown and throat patches appear velvety black. The very long, conspicuous side feathers project markedly at the sides, giving it an elongated “moustache” appearance.
- The back is metallic green. The plumage below is whitish with whitish-edged green feathers on the flanks.
- Small black tail and wings.
Adult Females
The female lacks the flashy cap and throat patch (gorget) of the male. Her throat is mostly white; however, some of them (the more mature females) have one or more purple / dark feathers in the center of the throat.
Her crown (fop of the head) and back are greyish-green.
Her chin and the plumage below are whitish. Her flanks are buffy-colored.
She has a dark tail with white tips on the outer tail feathers.
Hummingbird Resources
- Hummingbird Information
- Hummingbird Amazing Facts
- Attracting Hummingbirds to Your Garden
- Hummingbird Species
- Feeding Hummingbirds
Immatures:
Juveniles resemble the adult females. There is some grey-buff edging to the feathers of their upper plumage. The tail is doubly-rounded instead of singly-rounded.
They obtain their mature plumage when they are about one year old.
Similar Species:
- Black-chinned Hummingbirds:
- The males of both species have a throat patch (gorget). In good light conditions, the male Costa’s throat patch looks purple. The Black-chinned male’s gorget is mostly velvety black except for a glossy blue-violet band on the lower throat area, which could possibly cause some confusion. However, identification can still be readily made as only the male Costa’s has elongated throat feathers.The female Costa’s Hummingbird is very similar to the female Black-chinned Hummingbird, except the female Costa’s is whiter below than the Black-chinned female and their voices differ. Other than those differences, they are very difficult to tell apart.Both male and female Costa’s generally prefer a more arid terrain than the Black-chinned.
- Lucifer Hummingbirds:
- The adult male Lucifer Hummingbirds resembles the adult male Costa’s, but is easily separated in the narrow zone of overlap between the two species by its strongly down-curved bill, green crown and deeply forked tail.The female Lucifer is strongly buffy below and has a down-curved bill and forked tail.
- Anna’s Hummingbirds:
- The male Costa’s has a purple crown (top of the head) and throat patch while the male Anna’s Hummingbird has a reddish crown and gorget (throat patch). The male Costa’s gorget (throat feathers) are longer than that of the Anna’s. The female Costa’s is similar to the female and immature Anna’s, but the female Costa is typically is smaller, with a cleaner throat and whiter under plumage. The female Anna’s has a darker mottled grey under plumageBehavioral Differences:
Behavior:
Costa”s Hummingbirds territorial / aggressive behavior towards predators (such as other birds, snakes, mammals, including humans) includes a rapid dive at the predator and elaborate flight displays.
