A glittering green, iridescent, straight-billed hummingbird the size of a thrush or mockingbird – such would be an apt description of one of the more brilliant jacamars. These, however, are more closely related to woodpeckers, toucans, bar-bets, and puffbirds than to hummingbirds.
The jacamar’s long, slender, sharp bill seems poorly fitted for its aerial insect-catching niche and for excavating its nest chamber—a broad, flat bill would seem more efficient. However, the long bill can reach across the wings of a butterfly or dragonfly (which if seized might break and release the insect) to grasp the body firmly. Moreover, it keeps the flailing wings away from the jacamar’s face while it knocks its victim against a branch until the wings flutter earthward it also holds stinging wasps at a safe distance.
Jacamars appear to be charged with irrepressible vitality. While perching on an exposed twig above a stream, path, or open space in woods or thicket, they constantly turn their bright-eyed heads from side to side, looking for flying insects that they dart out to seize. The high, thin notes of their calls convey a sense of urgency. For birds that are not true songbirds, their vocal performances are surprisingly complex.
Jacamars nest in tunnels in which they dig in vertical banks or sloping ground or in hard, black termite mounds. The Rufous-tailed jacamar, the best-known species, may use both sites in the same locality. The male not only helps his mate to excavate but frequently feeds her, to the accompaniment of much singing.
The horizontal burrow,29-79cm (11-3 in) long, according to the species, ends in a chamber where 2-4 white eggs lie on the bare floor, which is soon covered by a growing accumulation of regurgitated beetles’ shards and other indigestible parts of insects. By day the sexes incubate alternately, often for an hour or two at a time.
The female occupies the nest by night. Unlike most birds of their order(Piciformes), the nestlings hatch with a thin coat of long white down. They are nourished wholly with insects by both parents and soon become loquacious, practicing the songs of the adults while they await their meals. Fledgling Rufous-tailed jacamars do not return to sleep in the burrow, but four young Pale-headed jacamars in Venezuela continued for several months to lodge with their parents in their longer tunnel.
The eight species of Galbula are a glittering golden green or purple glossed with green, with chestnut or white underparts. Exceptional in the family is the long-tailed Paradise jacamar of Amazonia and the Guianas with bronzy black plumage.
The Chestnut jacamar has a pink,kingfisher-like bill and the Three-toed jacamar of Brazil is a small bird with a chestnut head and blackish and grayish body. (Other jacamars have four toes, two directed forward and two backward.) The Great jacamar is a stout bird with a heavier bill, golden green, and rufous, like some of its smaller relatives.
Puffbirds are so named because their large heads, short tails, and often loose plumage give them a stocky aspect. Their bills are usually stout and hooked at the end, less often tapering and pointed. Their habit of resting motionless and often permitting close approach by humans causes the unperceptive to call them stupid.
Actually, they are wisely conserving energy, while with keen eyes they scrutinize surrounding vegetation. Suddenly they fly out, perhaps to snatch a green insect from green foliage 20 M (65ft) away.
Exceptional in the family are the swallow-wings, which are short-tailed, long-winged, blue-black birds with white rumps and cinnamon chestnut abdomens.
White-whiskered puffbirds are among the few species with sexual differences in plumage, the males being largely chestnut-brown and cinnamon, the females more olive and grayish. Although they live chiefly at mid heights of the rain forest, they nest in short, descending tunnels in the forest floor. On a bed of dead leaves, they lay two or three white eggs, which the female incubates through a long morning, the male for the remainder of the time. The blind, wholly naked nestlings are at first brooded by their father and fed by their mother. After daytime brooding ceases, the father helps to feed the nestlings for the remainder of their 20 days underground.
Most social puffbirds are the four species of nun birds. Their pointed, bright red or yellow bills contrast with their somber, black, or dark gray plumage. The calls of the White-fronted sunbird are extremely varied, ranging from wooden rattles to notes soft and deep. Up to io perch in a row on a high horizontal branch or vine and lift up their heads to shout all together, for 15 or 20 minutes, in loud, ringing voices.
Their long burrows in sloping or nearly level ground are lined with dead leaves and have collars of leaves and sticks around the entrance. Three or four adults, probably parents with older, nonbreeding offspring, feed three nestlings. Blind and naked, the nestlings toddle up the long entrance tunnel to receive their meals at the mouth. When about 3o days old they fly up into the trees.
The four species of Notharchus, boldly patterned in black and white, use stout black bills to carve nest chambers deep into hard, black termite mounds. Males and females share this task and later take turns incubating two or three white eggs on the online floor. Their notes are mostly weak and low. Species of Hueco and Hypnelus also breed in termite nests. The five species of nutlets are small nun-birds that range from Panama to N Argen-tina. Unobtrusive forest-dwellers colored gray, brown, cinnamon, and white, their habits are little known.
See more: Broadbills