White-necked jacobin  (Florisuga mellivora)

Classified as Least Concern (LC) on the IUCN Red List (1) and listed on Appendix II of CITES (3).

Like other members of the hummingbird family, the white-necked jacobin is remarkable for its dazzling plumage and unique wing structure, which makes it extremely adept at manoeuvring with incredible agility through the forest (4) (5). The male of this species has a shimmering blue head and chest, and bright iridescent green upperparts. This contrasts starkly with the snow white plumage of the belly, the broad white crescent on the back of the neck, and the white tail, which is tipped with black (2). The plumage of female white-necked jacobins is highly variable; a female may have the same plumage as a male, and only be distinguished by its longer bill and shorter wings and tail, or it may differ from the male by having blue-green on the breast, a dull white belly, and a mostly green tail with a dark blue tip (2). Both the male and female have black feet and a straight black bill (2) (6). Two subspecies of the white-necked jacobin are recognised, easily distinguished by their distribution, but also by the larger size of the subspecies Florisuga mellivora flabellifera (2).

The white-necked jacobin has a large distribution, ranging from southern Mexico, south to Bolivia and central Brazil (6). The subspecies F. m. mellivora is found throughout this range, including on the island of Trinidad, while subspecies F. m. flabellifera occurs only on the island of Tobago (2).

The clearings and edges of forest and woodland in humid lowlands are the preferred habitat for the white-necked jacobin (2) (6), although it may also be found in coffee and cacao plantations (2). It is most common from sea level up to an altitude of 900 metres, but occasionally can be seen up to 1,500 metres above sea level (2).

The beautiful white-necked jacobin is usually seen on its own in the forest, although occasionally small groups may gather, alongside other hummingbirds, at flowering trees (6). At these trees, the hummingbirds feed on nectar, probing the flowers with their long, specialised bills to obtain the sugar-rich liquid (5), and sometimes becoming aggressive as they compete for this valuable resource (2). The white-necked jacobin also feeds on flying insects, making short flights from its perch to snatch one from the air, or hovering in front of a swarm and picking them off one by one. It may also pluck its prey from leaves or branches (2) (6).

During the breeding season, the fantastic plumage of the male white-necked jacobin is most prominent, as it performs an attractive territorial display (6). A male will shoot up into the air, suddenly fan out its white tail, and then slowly descend as it steadily turns, displaying the tail in its full glory to a watching female (6) (7). Such displays often take place at considerable heights (6), up in the forest canopy (2). The white-necked jacobin nests in the forest understorey, one to three metres above the ground, where it constructs a shallow nest of soft vegetation and cobwebs on the surface of a broad leaf, which is sheltered from above by another large leaf (2).

The white-necked jacobin is not considered to be threatened with extinction, due to its large range (1), and its apparent ability to tolerate some level of habitat degradation, as it can inhabit disturbed areas, and man-made habitats such as tree plantations (2)

This hummingbird may be able to tolerate a degree of habitat degradation, but the species is also offered some reassuring protection within a number of National Parks, including Corcovado National Park in Costa Rica, Amacayacu National Park in Colombia, and Sierra Nevada National Park in Venezuela (2).

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the conservation of hummingbirds see:

• The Hummingbird Society:
  www.hummingbirdsociety.org

For more information on this and other bird species please see:

• BirdLife International:
  http://www.birdlife.org