Jacamars (Galbulidae)

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Jacamars

(Galbulidae)

Class Aves

Order Piciformes

Suborder Galbulae

Family Galbulidae


Thumbnail description
Slim tree birds, similar to an oversized hummingbird, with iridescent green plumage and long pointed bills

Size
5–12 in (13–31 cm)

Number of genera, species
5 genera; 17 species

Habitat
Neotropical forests

Conservation status
Endangered: 1 species; Vulnerable: 1 species

Distribution
Central and South America, from Mexico to Argentina

Evolution and systematics

With their brilliant colors and energetic ways, jacamars resemble hummingbirds but are actually related to puffbirds, toucans, and woodpeckers. Like all members of the order Piciformes, jacamars and their relatives have zygodactyl feet, with two toes pointing forward and two facing back. Jacamars evolved with this toe arrangement, which helps them grasp branches while hunting in trees. Jacamars, like woodpeckers and other piciform birds, are cavity nesters: they tunnel into the ground to build nests. Scientists believe jacamars are closely related to Old World bee-eaters, which also prey on flying insects, have similar plumage, and raise their young in the same manner.

Jacamars tend to live near lush tropical rainforests, which have a dazzling variety of large, colorful butterfly species. Jacamars have become highly selective predators. They often make their homes near streams, drilling nest cavities into steep banks and upturned tree roots.

Because 13 of the 17 Galbulidae species belong to super-species complexes, researcher J. Haffer concludes that jacamars had a relatively recent Pleistocene radiation of the family. Jacamars are believed to have originated in the Amazon region where they are most common, and spread to other parts of Central and South America. Unique anatomical features of this family include a long appendix, no gall bladder, a bare preen gland, and a long, thin tongue.

Physical characteristics

Wildlife enthusiasts treasure jacamars for their jewel-like colors. Their most distinctive characteristic is the long, sharp bill they use to snatch prey out of the air. In some species, the bill can be three times as long as the bird's head. Jacamars vary in size, from the brown jacamar (Brachygalba lugubris), at 7 in (18 cm) long, to the 1-ft-long (30 cm) great jacamar (Jacamerops aurea).

All jacamars, except one species, have short legs with four toes: two facing forward and two facing back. The three-toed jacamar (Jacamaralcyon tridaetyla), however, lacks the rear (first) toe. A jacamar has a long tail, with 10–12 graduated tail feathers. The short wings have 10 primaries, and contour feathers have a short secondary shaft (except in the genus Malacoptila).

Males and females have similar plumage, although females of some species may have less striking colors on the head and

neck. Jacamars, known for their brilliant plumage, typically have a metallic green head, reddish underparts, and a light patch on the throat or breast. Some species have color variations ranging from purple to red or chestnut brown. The paradise jacamar (Galbula dea) has much darker bluish black plumage with a contrasting white patch on the throat and a long, elegant tail.

While most newly hatched piciform birds are born naked, jacamars are covered with white down. By the time they leave the nest, plumage resembles that of the parents.

Jacamars are not songbirds, but A. Skutch has noted that they have loud calls, trills, and short songs that could be considered melodious.

Distribution

Jacamars occur mainly at low altitudes, ranging from southern Mexico to northern Argentina. The most widespread species, the rufous-tailed jacamar (Galbula ruficauda), occurs in Costa Rica, Trinidad, Mexico, Ecuador, Colombia, Brazil, and Argentina. The distinctive great jacamar ranges from Costa Rica to the Amazon basin. The green-tailed jacamar (Galbula galbula) is found north and south of the Amazon. More rare is the coppery-chested jacamar (Galbula pastazae), which has a low population. It has been observed at a small number of sites in southern Colombia and along the slopes of the Ecuadorian Andes.

Habitat

Jacamar habitat includes Neotropical rainforests, streams or riverine forest, and savanna woodland. Generally, jacamars live at the edge of forests. Jacamars prefer habitat that supports their favorite prey—large, showy butterflies. Suitable nesting sites, such as dirt masses associated with fallen trees and sandy or clay stream banks, also are key. The rufous-tailed jacamar prefers low-lying thickets that border rivers, while the paradise jacamar seeks a higher perch. The coppery-chested jacamar lives at the highest elevations of all jacamars. It has been observed at altitudes of 5,100 ft (1,550 m) in the Andes. It is a resident of the eastern slope of the Ecuadorian Andes, although its distribution is patchy, and its population is dwindling due to habitat loss.

Behavior

Jacamars are exciting to watch because they are dramatic acrobats, swooping down from perches to capture colorful prey in mid-air. They spend most of their time on a branch, alert and scanning the air for flying insects.

Typically, jacamars live in pairs that perch and hunt in the same area. Certain species will occasionally congregate in small family groups. Unlike other jacamar species, the yellow-billed jacamar (Galbula albirostris) often joins mixed flocks of birds. Jacamars use a variety of calls to communicate. For example, rufous-tailed jacamars signal danger or agitation with a sharp trill.

Feeding ecology and diet

As an entirely insectivorous family, jacamars prefer large, showy, flying insects. Their diet consists of butterflies, moths, wasps, dragonflies, and flying beetles. A long, forceps-like bill allows the jacamar to grasp its prey while keeping it at enough of a distance to avoid becoming blinded by fluttering wings or injured by a stinging insect. Once they catch an insect, jacamars batter it against a tree branch to kill it, and remove the wings before swallowing.

Favorite food sources include beautiful blue morpho butterflies, hawk moths, and venomous Hymenoptera such as bees and wasps. Skutch also observed a preference for butterflies and dragonflies. In his work, Chai described how young rufous-tailed jacamars in Costa Rica learned to discriminate between butterfly species by color, markings, and flight patterns. Jacamars tend to reject butterflies with chemical defenses that make them less palatable. With their specialized hunting skills, jacamars may have played a major role in the evolution of butterflies that live in jacamar habitats.

Reproductive biology

During breeding season, male jacamars engage in lively vocal performances, with a series of explosive, sharp calls. Two rival males use this display of courtship and verbal bravado to impress a potential mate. Jacamars form monogamous pairs.

Jacamars dig holes for nests in steep river banks. They use the bill to break up the soil, then remove it by kicking backwards with their feet as they burrow. These tunnels also can be found some distance from the water, on soil banks or roots of fallen trees. The nest sits at the end of the tunnel in a horizontal, oval-shaped terminal chamber. Some jacamars, including the rufous-tailed jacamar, may use termite nests for breeding if no appropriate site to dig a ground tunnel can be found. Tunnels are 12–36 in (30–91 cm) long and about 2 in (5 cm) in diameter. The nest chamber is used repeatedly and does not contain nest material, although eggs often are covered with a layer of regurgitated insect parts. In some species, male and female participate in building the nest hole; in other species only the female does this work.

Jacamars lay one to four round, glossy, white eggs. Both parents incubate the eggs during the day for one to three hours at a time. At night, the female incubates alone while the male stays nearby to defend the nest. Jacamars rarely leave eggs unattended. During incubation, the male feeds his partner several times each day. The incubation period is 20–23 days.

Both parents feed the young with insects. Chicks remain in the nest 21–26 days. Unlike other species, young pale-headed jacamars (Brachygalba goeringi) may return to the burrow to sleep with the parents for several months after they fledge.

Conservation status

Habitat loss is a continuing threat to jacamars. In Brazil, intensive clearance of understory vegetation in forest fragments caused a decline of jacamar populations, along with an overall lack of bird species diversity in the area.

Only one jacamar species, the three-toed jacamar, is classified as Endangered. This species prefers lowland tropical rainforest, plantations, tropical monsoon, and dry forest. The three-toed jacamar used to thrive in southeast Brazil, including eastern Minas Gerais, Espírito Santo, Rio de Janeiro, São Paulo, and Paraná. Development and agricultural land use have destroyed much of its habitat. The remaining population, restricted to Rio Paraíba valley in Rio de Janeiro and the dry regions of Minas Geraís, is small and fragmented. The three-toed jacamar is protected under national law in Brazil. The Caratinga Reserve in Brazil offers a safe haven for this endangered species.

The coppery-chested jacamar—found in montane tropical rainforests of Colombia, Ecuador, and Amazonian Brazil—is classified as Vulnerable. Its total population is believed to be small and declining due to destruction of its forest habitat.

Significance to humans

The Tupi, an indigenous population in Brazil, gave the jacamar its name. It is derived from a Tupi word, jacama-ciri. Over the years, people in the region have given this popular bird nicknames such as "bico-de-agulha" (needle bill) and "beija-flor grande" (big hummingbird).

Species accounts

List of Species

Rufous-tailed jacamar
Green-tailed jacamar
Great jacamar
Three-toed jacamar
Coppery-chested jacamar
Paradise jacamar
Yellow-billed jacamar

Rufous-tailed jacamar

Galbula ruficauda

taxonomy

Galbula ruficauda Baron Cuvier, 1816.

other common names

French: Jacamar à queue rousse; German: Rotschwanz-Glanzvogel; Spanish: Jacamar Común.

physical characteristics

9 in (23 cm); 2 in (51 mm) slender bill. Metallic green upper parts, white or buff patch on throat, rufous or reddish underside.

distribution

Very common from southern Mexico to northern Argentina, including Brazil, Colombia, and Ecuador. Also found in Trinidad and Tobago.

habitat

Forest edge, woodland, thickets, and near streams and rivers.

behavior

Live in pairs, prefer to hunt from low shrubbery.

feeding ecology and diet

Prefers flying insects, like most jacamars. Catches prey in midair and batters it against a branch before consuming it.

reproductive biology

Lays one to four white eggs in ground-hole nest cavity. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days. Both sexes incubate, and care for chicks.

conservation status

Not threatened; widespread and common, adapts to many different habitats.

significance to humans

None known.


Green-tailed jacamar

Galbula galbula

taxonomy

Galbula galbula Linnaeus, 1766.

other common names

French: Jacamar vert; German: Grünschwanz-Glanzvogel; Spanish: Jacamar de Cola Verde.

physical characteristics

8 in (20 cm); 2 in (51 mm) slender bill. Metallic green upper-parts, white or buff patch on throat, tail shorter and more rounded than other species, with green on top and dusky blue underneath.

distribution

Brazil, Colombia, the Guianas, and Venezuela.

habitat

Forest edge, woodland, usually close to water.

behavior

Like rufous-tailed jacamar, they prefer lower shrub perches for hunting.

feeding ecology and diet

Prefer butterflies and dragonflies. Catches prey in mid-air and batters it against a branch before consuming it.

reproductive biology

Lays one white eggs in ground-hole nest cavity. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days, covered in white down. Both sexes incubate and care for chicks.

conservation status

Not threatened.

significance to humans

None known.


Great jacamar

Jacamerops aurea

taxonomy

Jacamerops aurea Müller, 1776.

other common names

French: Grand jacamar; German: Breitmaul-Glanzvogel; Spanish: Jacamar Grande.

physical characteristics

The largest jacamar: 12 in (30 cm) long, with thick, slightly curved bill. Metallic green upperparts, white narrow band on throat, rufous underside, with bluish black underside of tail.

distribution

Venezuela, Ecuador, Costa Rica, Bolivia, and Amazonian Brazil.

habitat

Riverine forest, lowlands.

behavior

Quieter and slower moving than other jacamar species. Known for its mournful-sounding call.

feeding ecology and diet

Preys on flying insects. Catches prey in mid-air and batters it against a branch before consuming it.

reproductive biology

Lays one to four white eggs in ground-hole nest cavity. Incubation is 20–23 days. Chicks emerge from nest after 21–26

days, covered in white down. Both sexes incubate, and care for chicks.

conservation status

Not threatened.

significance to humans

None known.


Three-toed jacamar

Jacamaralcyon tridactyla

taxonomy

Jacamaralcyon tridactyla Vieillot, 1817.

other common names

French: Jacamar tridactyle; German: Dreizehen-Glanzvogel; Spanish: Jacamar Tridáctilo.

physical characteristics

7 in (18 cm); 0.7 oz (20 g). Has three toes, two facing forward and one back; dark grayish green plumage and a chestnut-brown head.

distribution

Southeastern Brazil.

habitat

Open woodland, lowlands.

behavior

Similar to kingfishers in hunting behavior, color, and beak shape.

feeding ecology and diet

Prefers flying insects. Perches on tall grasses at the edge of forest to watch for prey, then darts out and catches it in mid-air.

reproductive biology

Lays one to four white eggs in ground-hole nest cavity. Sometimes nests colonially. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days, covered with white down. Both sexes incubate, and care for chicks.

conservation status

The only Endangered jacamar species, due to habitat loss from agriculture and development. The current population is not known, but has declined dramatically and is believed to exist in very small numbers. Three-toed jacamars are protected in the Caratinga Reserve in Brazil.

significance to humans

None known.


Coppery-chested jacamar

Galbula pastazae

taxonomy

Galbula pastazae Taczanowski and Berlepsch, 1885.

other common names

French: Jacamar des Andes; German: Kupferglanzvogel; Spanish: Jacamar Cobrizo.

physical characteristics

9 in (23 cm) long. Heavier 2 in (51 mm) bill. Metallic green upperparts, dark rufous throat, copper tail, distinctive yellowish orange eye ring.

distribution

Colombia, Ecuador, and Amazonian Brazil.

habitat

Lives in the highest forest elevation of all jacamar species.

behavior

Alert hunter, similar to other jacamars. Gives a series of three to five loud calls.

feeding ecology and diet

Diverse variety of flying insects. Prefers to hunt from one favorite perch, capturing insects as they fly through the air.

reproductive biology

Lays one to four white eggs in curved ground-hole nest cavity, so eggs are out of view. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days, covered with white down. Both sexes incubate and care for chicks.

conservation status

Vulnerable; thin distribution, low population limited to a few locations, primarily in Colombia and the east slope of the Andes. Threatened by deforestation.

significance to humans

None known.


Paradise jacamar

Galbula dea

taxonomy

Galbula dea Linnaeus, 1758.

other common names

French: Jacamar à longue queue; German: Paradeisglanzvogel; Spanish: Jacamar de Cola Larga.

physical characteristics

12 in (30 cm) long; 2 in (51 cm) slender bill. Metallic bluish black color on upper and lower body, contrasting white patch on throat, long elegant tail.

distribution

Amazonian Brazil, the Guianas, Peru, Bolivia, Venezuela, and Ecuador.

habitat

Forest and forest edge or upland woodland.

behavior

Hunts alone, in pairs, or in groups of three, may join canopy flocks.

feeding ecology and diet

Prefers butterflies and dragonflies. Perches on a branch, then darts out to capture prey in mid-air.

reproductive biology

Lays one to four white eggs in ground-hole nest cavity. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days, covered in white down. Both sexes incubate, and care for chicks.

conservation status

Not threatened.

significance to humans

None known.


Yellow-billed jacamar

Galbula albirostris

taxonomy

Galbula albirostris Latham, 1790.

other common names

English: Blue-cheeked jacamar; blue-necked jacamar; French: Jacamar à bec jaune; German: Gelbschnabel-Glanzvogel; Spanish: Jacamar de Pico Amarillo.

physical characteristics

7.5 in (19 cm) long. The only jacamar species with a yellow bill. Metallic green on upperparts, purplish brown head, white patch on throat, rufous on underparts and tail. Feet and eye ring are yellow.

distribution

Amazonian Brazil, the Guianas, Peru, Venezuela, Colombia, and Ecuador.

habitat

Prefers forest interior more than most jacamars.

behavior

Often joins mixed flocks of other bird species.

feeding ecology and diet

Prefers butterflies and dragonflies. Captures flying insects while hunting from a perch.

reproductive biology

Lays one to four white eggs in ground-hole nest cavity. Incubation is 20–23 days. Chicks emerge from nest after 21–26 days, covered with white down. Both sexes incubate, and care for chicks.

conservation status

Not threatened.

significance to humans

None known.


Resources

Books

Hilty, Steven L., and William L. Brown. A Guide to the Birds of Colombia. New Jersey: Princeton University Press, 1986.

Janzen, Daniel H., ed. Costa Rican Natural History. Chicago: University of Chicago Press, 1983.

Periodicals

Chai, P. "Butterfly Visual Characteristics and Ontogeny of Responses to Butterflies by a Specialized Tropical Bird." Biological Journal of the Linnean Society 59, no. 1 (1996): 37–67.

Chai, P. "Field Observations and Feeding Experiments on the Responses of Rufous-tailed Jacamars to Free-flying Butterflies in a Tropical Rainforest." Biological Journal of the Linnean Society 29, no. 3 (1986): 161–189.

Marsden, Stuart, J., Mark Whiffin, and Mauro Galetti. "Bird Diversity and Abundance in Forest Fragments and Eucalyptus Plantations Around an Atlantic Forest Reserve, Brazil." Biodiversity and Conservation 10, no. 5 (2001): 737–751.

Organizations

Neotropical Bird Club. c/o The Lodge, Sandy, Bedfordshire SG19 2DL United Kingdom. E-mail: secretary @neotropicalbirdclub.org Web site: <www.neotropicalbirdclub.org>

Other

Caratinga: Soundscapes from Brazil's Atlantic Rainforest. Compact disc, Earth Ear Catalog, 2001. Available online at <http://www.earthear.com/catalog/caratinga.html>

The IUCN Red List of Threatened Species. Species Information: Three-toed Jacamar. <http://www.redlist.org>

Melissa Knopper, MS