The Bee hummingbird is the world's smallest bird. Compared to other small hummingbirds, which often have a slender appearance, the Bee hummingbird looks rounded and plump. The male has a green pileum and bright red throat, iridescent gorget (colored feathers on the throat) with elongated lateral plumes, bluish upperparts, and the rest of the underparts mostly greyish white. The female is bluish-green with a pale gray underside. The tip of its tail feathers has white spots.
Bee hummingbirds are native to the entire Cuban archipelago, including the main island of Cuba and the Isla de la Juventud in the West Indies. They live in rainforest, dry forest and at forest edges with bushes and lianas. They can also be found in mountain valleys, swamplands, and gardens.
Bee hummingbirds are sedentary and only make short movements to the nearby islands. They lead a solitary life and are very territorial on their feeding areas aggressively chasing away intruders. Bee hummingbirds are active during the day; they feed mainly on nectar, and an occasional insect or spider, by moving their tongue rapidly in and out of their mouth. Like all hummingbirds, they are swift, strong fliers and are able to fly straight up, down, backward and even upside down. Bee hummingbirds communicate with each other using high-pitched songs squeaking and twittering sounds and make “tsit” calls while feeding.
Bee hummingbirds are polygynous; they don't form pairs and a single male may mate with more than one female during the breeding season. These birds breed between March and June. Males perform aerial displays and sing songs to attract females. The female alone constructs the nest incubates the eggs and raises her young. Using bits of cobwebs, bark, and lichen, the female builds a cup-shaped nest that is about 2.5 cm (0.98 in) in diameter. She lines the nest with soft plant fibers. There she lays 2 eggs, which are no bigger than peas and incubates them within 21-22 days. The chicks are altricial; they hatch naked, with reddish bodies and closed eyes. They fledge at 18-38 days after hatching and reach reproductive maturity at 1 year of age.
The main threat to Bee hummingbirds is habitat loss due to the destruction of native vegetation for agriculture. These small birds also suffer predation from tropical spiders, frogs, fish, and larger birds.
The IUCN Red List and other sources don’t provide the number of the Bee hummingbird total population size. Currently, this species is classified as Near Threatened (NT) on the IUCN Red List and its numbers today are decreasing.
Bee hummingbirds play an important role in their ecosystem. During the feeding time, these birds pick up pollen on their bills and heads. When they fly from flower to flower, they transfer the pollen and this way assist in plant reproduction.