The Green-throated Carib (Eulampis holosericeus) is a species of hummingbird found in the Caribbean. With its emerald green throat and upper breast, it is one of the most brightly colored hummingbirds in the world. This medium-sized hummingbird reaches lengths of 10-12 cm and weighs 5-8 grams.
Range and Habitat
The Green-throated Carib is found on islands throughout the Caribbean including the Greater Antilles, Lesser Antilles, Bahamas, Turks and Caicos, and Cayman Islands. Its range extends from the Virgin Islands in the north down through the Leeward Islands, Windward Islands, Barbados, and Grenada. It is estimated there are between 10,000-100,000 Green-throated Caribs in the wild.
This species occupies a variety of habitats across its range including forests, woodland edges, gardens, plantations, and mangroves. It thrives in areas with plenty of flowering plants and sources of nectar. The Green-throated Carib prefers lower and middle elevations up to 1500 m.
Physical Description
The Green-throated Carib is a stunning, medium-sized hummingbird with vibrant green plumage on its throat and upper breast. The throat ranges from emerald to lime green. The upperparts are mostly golden green. The belly and undertail are white. The tail is forked and metallic blue-black with white outer tail feathers. The male’s gorget (throat feathers) are iridescent, often appearing to change color in different lighting.
The bill of the Green-throated Carib is fairly long, straight, and black. Legs and feet are also black. Their eyes are brown. Males and females look alike, though young birds have some buffy edging to their plumage. Males are slightly larger than females.
Diet and Feeding
Like all hummingbirds, the Green-throated Carib feeds on nectar from flowers and flowering trees. Some of its favorite nectar sources are Heliconia flowers, hibiscus, and various orchids and bromeliads. The long bill is perfectly adapted for reaching nectar at the base of long, tubular flowers. Besides nectar, these hummingbirds will eat small insects for essential proteins.
When feeding, the Green-throated Carib hovers in front of the flower, extending its long tongue into the bloom to lap up nectar. Its wings beat extremely fast, allowing it to hover and change direction with ease. The Green-throated Carib will aggressively defend flower patches as its preferred feeding grounds, chasing away other hummingbirds or insects.
Unique Adaptations
The Green-throated Carib has special physical adaptations that allow it to thrive as a nectar-feeding bird. Here are some of its most unique features:
– Tiny size with high metabolism – By being so small, the Green-throated Carib expends relatively little energy hovering and lapping nectar. Its high metabolism powers its constant activity.
– Rapid wing beats – Its wings beat up to 70 times per second, allowing effortless hovering and maneuverability. Primary flight feathers rotate like tiny helicopters.
– Long, specialized tongue – The tongue extends to reach nectar. It has tube-likeChannels that suck up nectar. The tongue tip is forked to lap nectar efficiently.
– Bill shape – The long, slim bill is adapted perfectly for probing flowers and accessing nectar from slender corollas. The black color may help absorb heat.
– Feather iridescence – Throat feathers refract light, producing brilliant, shimmering colors. This may attract mates.
– High sugar diet – The carbohydrate-rich nectar provides energy for endless hovering and activity. Kidneys efficiently eliminate excess water.
– Energy efficiency – At rest, hummingbirds go into torpor to conserve energy. Their minimal body fat provides insulation and emergency energy reserves.
Unique Behavior
The Green-throated Carib displays some interesting behaviors related to feeding, courtship, migration, and more:
– Traplining – Individuals establish regular routes to visit preferred flower patches. They will aggressively defend these nectar sources.
– Nectar robbing – At some flowers, caribs will chew holes at the base to access nectar rather than pollinating properly.
– Pugnacity – Males will aggressively chase other males or birds that approach their territory and food sources. They often perch conspicuously to guard territory.
– Courtship displays – Males perform elaborate dives, aerial loops, and hovering rituals to impress females. The iridescent throat is shown off.
– Residency – Populations in the northern Caribbean are migratory, while birds in the south are mostly year-round residents.
– Sun basking – Caribs bask in sunlight to warm their bodies in cool temperatures. Wings are extended to expose the surface area.
– Torpor – To conserve energy, caribs reduce their temperature and metabolic rate during their nightly rest period.
Reproduction and Lifespan
The breeding season for Green-throated Caribs varies across their range, generally coinciding with periods of abundant flowers. In the northern Caribbean, breeding occurs from March to June. Farther south, breeding can occur year-round.
Males court females with elaborate aerial displays over their flower territory, flying in loops and dives to show off their iridescent throat patch. Once paired, the female builds a small cup nest out of soft plant down, spider webs, and lichens, attached to a branch or vine. She incubates the two tiny white eggs for 15 to 19 days.
Chicks hatch with eyes closed and almost no feathers. They develop quickly on a diet of regurgitated nectar and insects from the parents. They fledge at about 18-23 days old. The female cares for the chicks with no assistance from the male. Green-throated Caribs may raise 2-3 broods per year.
Threats and Conservation
The Green-throated Carib is widely distributed across the Caribbean islands but faces some concerning threats:
– Habitat loss – Development, logging, and agriculture reduce native vegetation and flowers needed for food.
– Invasive species – Introduced bees, ants, and snakes compete for nectar sources and prey on eggs. Mongoose and cats prey on adults.
– Pesticides – Chemical use can reduce insect prey. Nectar and pollen may become contaminated.
– Climate change – Rising temperatures and extreme storms may threaten populations. Ranges may shift.
– Pollution – Urban and agricultural chemicals pollute the environment for hummingbirds.
Despite these threats, the Green-throated Carib remains relatively abundant due to its adaptability. Some specific conservation actions include:
– Protecting intact forests through parks and reserves.
– Promoting native plants, especially endemic species the carib relies on.
– Controlling invasive species like ants that disrupt native ecosystems.
– Monitoring populations and research to identify threats.
– Raising awareness and supporting ecotourism to see magnificent hummingbirds.
With continued conservation, the colorful and energetic Green-throated Carib will continue dazzling bird enthusiasts as it zips among tropical flowers across the Caribbean. The unique adaptations and behaviors of hummingbirds never cease to impress. Protecting their habitat ensures we can continue observing their aerial displays and enjoying their jewel-colored beauty.