The White-necked Jacobin (Florisuga mellivora) is a medium-sized hummingbird found in tropical regions of Central and South America. With its shiny blue-green back, bright white underparts, and distinctive white streak on its neck, the white-necked jacobin is one of the more colorful and eye-catching hummingbird species.
Physical Description
The white-necked jacobin averages 11-12 centimeters in length and weighs around 6-8 grams. As its name suggests, the most distinctive feature of this species is the conspicuous white stripe or streak that runs along the sides of its neck. The upperparts and head are a glossy blue-green, while the underparts are bright white. The tail is forked and a deep blue-black in color. The long bill is black, slightly decurved, and adapted for drinking nectar from flowers.
Males and females have similar plumage, although females may have some white spotting on their throats. Juveniles are duller in color and lack the striking white neck streak of adults. The white neck feathering develops as the birds mature.
Geographic Range and Habitat
The white-necked jacobin is found from southern Mexico south through Central America to Bolivia, Brazil, and central Argentina. Its natural habitats are lowland and foothill tropical forests, second growth woodlands, plantations, parks, and gardens.
This species has adapted well to human disturbance and is common in agricultural areas and other open, partially cleared lands at the borders between forests and human settlements. It occurs up to elevations of around 1600 meters in the Andes Mountains.
Diet and Feeding
Like all hummingbirds, the white-necked jacobin feeds mainly on nectar taken from a variety of brightly colored, scented tropical flowers. Some favorite food plants include shrubs and small trees like Inga, Calliandra, and Pithecellobium. This species can often be found feeding in gardens, visiting ornamental flowers and plants.
The long decurved bill of the white-necked jacobin allows it to access nectar from flowers with corollas of various shapes and sizes. While feeding, these hummingbirds hover in front of the flower and extending their tongues to lap up nectar. They also take some small insects and spiders to obtain proteins and other nutrients.
Reproduction and Breeding
The breeding season of the white-necked jacobin varies across its range, generally coinciding with periods of rainfall and flower abundance. Males are polygynous, mating with multiple females. The males perform courtship displays, flying in looping U-shaped patterns to impress females.
Females build a small cup-shaped nest out of plant fibers and spider webs on a tree branch, usually 2-15 meters above ground. The nest is lined with soft plant down. The female lays two tiny white eggs. She incubates the eggs alone for 15-19 days until they hatch. The chicks are fed regurgitated food by the female and fledge in about 20-26 days.
Behavior
White-necked jacobins often feed at mid-levels in gardens and open areas, perching on low branches between foraging bouts. Despite their bright plumage, they can be rather inconspicuous as they tend to remain concealed in foliage, darting out to visit a flower.
Males are highly territorial, chasing away other hummingbirds from their feeding areas. They perform singing displays during the breeding season, making a repeated clicking sound with their beaks to attract mates.
This species is sometimes seen among mixed flocks of small songbirds like tanagers. It benefits from the presence of other birds that flush insects for it to pick off. Roosting at night helps conserve energy reserves.
Conservation Status
With a relatively extensive range and stable population trend, the white-necked jacobin is evaluated as a species of Least Concern on the IUCN Red List of Threatened Species. Despite some habitat loss across its range, it remains common in many protected areas and modified landscapes. As long as suitable flowers and nest sites are available, this adaptable hummingbird should continue thriving. More research is needed to estimate its total population numbers in the wild.
The white-necked jacobin’s resilience shows how some tropical species can adapt to coexisting with humans, provided small fragments of habitat are left intact. This charismatic hummingbird brings joy to backyard birders wherever it occurs, and conserving natural areas will ensure future generations can continue to enjoy its beauty. With appropriate environmental stewardship, this jacobin and many other hummingbirds will continue brightening the forests of the Neotropics.