Hummingbirds are some of the most fascinating birds to observe in nature. There are over 300 different species of hummingbirds, all located in the Americas. Hummingbirds are well known for their ability to hover in midair and fly backwards, making them highly agile flyers. Their extremely fast metabolisms require them to consume nectar frequently throughout the day. While observing hummingbirds can be thrilling, it can also be challenging to distinguish between males and females of the same species. However, with some key identification tips, you’ll be able to tell males and females apart in no time.
Differences in Appearance
The most noticeable difference between male and female hummingbirds is often color. In many species, the males have vibrant, iridescent plumage in shimmering hues while females have more muted tones in their feather coloring. The contrast can be striking – take the Anna’s Hummingbird for example. The male has a bright rose-pink throat and crown, and a vibrant green back. The female Anna’s Hummingbird is primarily grey-green in coloration. This more subdued appearance helps provide camouflage for the female as she incubates her eggs.
Males also tend to have more elaborate plumage with bright patches, stripes, or tail feathers used to attract females. Some commonly seen ornamental feathers on the male include elongated tail feathers, tufts, and colorful throat patches called gorgets. Females lack these flashy plumage traits. The elegant, streamlined appearance of the female hummingbird contrasts sharply with the showy feathers and accessories of the males.
Examples of Differences in Appearance
| Species | Male Appearance | Female Appearance |
|---|---|---|
| Anna’s Hummingbird | Bright rose pink throat, green crown and back | Grey-green overall color |
| Ruby-throated Hummingbird | Ruby red throat | White throat with some small red markings |
| Rufous Hummingbird | Deep rusty red throat patch, boldly striped tail | Pale rust colored throat, no tail stripes |
| Broad-tailed Hummingbird | Magenta throat with a slightly forked tail | Pale throat, square tail with white tips |
The colorful plumage on males is the result of sexual selection, where females preferentially select the most vibrant and decorated males during mating. Over many generations, the bright colors and elaborate feathers evolved to give males a reproductive advantage. Females do not need these embellishments to attract a mate, allowing them to retain more inconspicuous, practical plumage.
Differences in Size
In addition to varied plumage, male hummingbirds tend to be slightly larger than females of the same species. The difference is most pronounced in the bill and tail. Male hummingbird bills are often longer, straighter and more needle-like compared to females. This adaptation allows access to nectar from longer, more curved flowers. The tail shape also diverges between sexes, with males having larger, wider tail surfaces relative to body size. Researchers hypothesize more expansive tails give males greater maneuverability and aerial agility, useful during competitive mating flights and displays.
Mass and wingspan follow similar trends, with males measuring very slightly larger than females. However, the differences are typically not substantial enough to be a reliable method for sexing individual birds in the field. On average, expect the total hummingbird length of males to be up to 10% greater than females. Any outliers from this range could be due to natural variation and not indicative of sex.
Examples of Differences in Size
| Species | Male Mass (g) | Female Mass (g) | Male Wingspan (cm) | Female Wingspan (cm) |
|---|---|---|---|---|
| Calliope Hummingbird | 2.4 – 3.1 g | 2.3 – 3.0 g | 8 – 9 cm | 7 – 8 cm |
| Rufous Hummingbird | 3.1 – 3.4 g | 2.6 – 3.3 g | 8 – 9 cm | 7 – 8 cm |
| Ruby-throated Hummingbird | 2.4 – 4.3 g | 2.4 – 4.1 g | 8 – 11 cm | 8 – 10 cm |
| Black-chinned Hummingbird | 2.5 – 3.5 g | 2.3 – 3.4 g | 8 – 10 cm | 7 – 9 cm |
Keep in mind these size ranges overlap substantially, so size on its own should not be used as conclusive evidence for determining sex. Use relative size differences as supporting information in conjunction with other sexing criteria.
Differences in Behavior
Certain courtship rituals and territorial behaviors can also help cue identification of males. During the breeding season, males perform elaborate courtship displays, flying in loops and dive displays to impress females. They also vigorously defend feeding territories, chasing competing males from their area. Females do not partake in these behaviors, focusing their energies instead on nest construction, egg laying and caring for young.
In non-breeding seasons, the behaviors between sexes overlap more significantly. However, males can still be spotted temporarily staking claim over prime nectar sources in a feeding area. They allow females to share these food resources while aggressively repelling other males.
Additionally, adult males spend more time vocalizing with communication calls and songs to declare territory ownership and court females. So frequent chirping and vocalizing from a hummingbird perch is indicative of a male. Females vocalize less outside of the breeding season.
Differences in Habitat Use
Habitat separation between the sexes after breeding season can also make locating and identifying males easier. As fall migration approaches, males depart the breeding grounds first and begin migrating south up to a few weeks earlier than females. This adaptation perhaps helps secure the best winter territories.
During winter months, males can be found concentrated along the Gulf Coast and other more subtropical climates farther south. Females overwinter slightly farther north on average and scatter out over a broader range. Searching for hummingbirds in these more southern winter grounds increases your chances of observing males. Focus on habitats with red tubular flowers and nectar feeders as these are particularly attractive foraging sites for adult males establishing winter territories.
How to Distinguish Immature Birds
All the guiding principles above apply specifically to adult male and female hummingbirds. Identifying the sex of younger, immature hummingbirds brings additional challenges.
Young birds freshly out of the nest resemble adult females both in size and plumage coloration. Without full adult feathers, they lack any bright patches or flashy accents. The best strategy is observing size and behavior over time. If a small hummingbird with female-like plumage repeatedly displays territorial aggression and courtship behavior, you can confirm it is a young male. His coloration will gradually shift to adult male features.
Immature females look almost identical to mature females. Focus on size as your main metric. Young females measure smaller in total length and mass compared to adults. By establishing regular observation of banded birds over the course of multiple seasons, you can witness young females gradually attain their mature size.
Conclusion
Telling males and females apart is an essential skill for observing hummingbirds and understanding their ecology. With keen observation of key differences, identifying the sexes is completely achievable. Focus on comparing color patterns, feather accents, proportions, actions, habitat use, and vocals to accurately tell males from females. Pay close attention through the seasons as hummingbirds mature and exhibit their definitive sex-specific traits. Soon you’ll be a pro at distinguishing subtle variations between the sexes in your local hummingbird community.
