Toucans (Ramphastidae)

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Toucans

(Ramphastidae)

Class Aves

Order Piciformes

Family Ramphastidae


Thumbnail description
Medium-sized to large birds, instantly recognizable by their strikingly large and colorful bills; often associate in small flocks when foraging

Size
13–24 in (33–60 cm); 4–30 oz (113–850 g)

Number of genera, species
6 genera; 41 species

Habitat
Predominately tropical and montane rainforest

Conservation status
Endangered: 1; Near Threatened: 3

Distribution
South America south to northern Argentina

Evolution and systematics

The toucans (Ramphastidae) are a very striking group. No fossilized remains of this family are known; recent remains of a toco toucan (Ramphastos toco), from the Pleistocene (20,000 years old) have been found, in Minas Gerais, Brazil.

The toucans' closest relatives are barbets (Capitonidae), and the two groups are thought to have evolved from a common ancestor; in their landmark 1993 study, Sibley and Ahlquist describe toucans as "New World barbets with big bills." Woodpeckers (Picidae) are closely allied to the toucans, which are also similar to hornbills (Bucerotidae), albeit more distantly related.

J. Haffer proposed the most widely accepted theory of speciation in toucans, and his model has since been applied to other Amazonian bird groups. Toucan speciation apparently occurred during Pleistocene glaciations (characterized by dry forest expansions) and interglaciations (characterized by tropical forest expansions). The rapid formation and disappearance of new Pleistocene biomes enhanced speciation rates in this region. Species derived from drier biomes later became sympatric (inhabiting the same range but not interbreeding) when tropical forest expanded in Amazonia, forcing the dry forest specialists to adapt to tropical forest or perish. There are 6 genera with 41 species. The green toucanets (Aulacorhynchus) are represented by seven species; the aracaris (Pteroglossus) by 12 species; the black toucanets (Selenidera) by six species; the saffron toucanet (Baillonius) is monotypic and in Peters is lumped into genus Andigena; the mountain toucans (Andigena) are represented by four species; and the true toucans (Ramphastos) by 11 species.

Social mimicry, a relatively rare evolutionary event in nature, is seen in this group. Social mimicry is the situation in which two or more distantly related species are more similar to one another than they are to other, more closely related species. Among toucans, it is apparent in the yellow-ridged toucan (Ramphastos vitellinus culminatus), which mimics the color and appearance of the larger white-throated toucan (Ramphastos tucanus cuvieri). The mimic benefits because it avoids being attacked by the larger model, while its appearance deters smaller species from trying to share feeding sites.

Physical characteristics

Toucans are characterized by brightly colored plumage and an unusually long and bulky, but very lightweight, bill

with a downcurved tip and serrated edges. Another trait characteristic of toucans is a tongue with a bristly or brushy tip. Toucans range in length from 13–24 in (33–60 cm). In almost all species, male and female look alike; only the black toucanets (Selenidera) and green aracari (Pteroglossus viridis) are sexually dimorphic.

The toe arrangement is zygodactylous, with two toes projecting towards the front and two to the back.

Naturalists have long puzzled over the significance of the toucan's large bill. Originally, observers suggested that the bill was a weapon used to defend the nest cavity. This is not so; when toucans sense danger, they come out of the cavity entrance in a hurry, threatening the enemy only out in the open, if at all. Instead, a long bill enables these rather heavy birds to pluck berries from the tips of branches without leaving a stable perch. A thin, dark-colored bill would, however, be just as useful for this purpose. Possibly the toucan's bill plays a role in pair formation and in the social life of the group. According to E. Thomas Gilliard, it acts as a signal. However, toucans can also use their bills to threaten those birds whose nests they plunder. Tyrant flycatchers and even small raptors are frightened by the giant bill, which is even more effective because of its lively colors, and they fly about helplessly while the toucans devour their young or eggs. Other birds will attack a toucan only while it is in flight, because it is then unable to defend itself with its bill.

Distribution

Toucans are restricted to the Neotropics, where they are distributed through most of tropical South America as far as northern Argentina, with some individuals found as far north as Mexico. Although most species are lowland residents, there are some exceptions: most of the toucanets (Aulacorhynchus) have home ranges at 8,200 ft (2,500 m) or higher in Central America, and the mountain toucans (Andigena) range 3,900– 11,000 ft (1,200–3,350 m) in the South American Andes.

The nation with by far the highest diversity of toucans is Colombia, with 21 species; Venezuela, Ecuador, and Brazil are home to 17 species each. The country with the lowest diversity of toucans is Trinidad, with a single species, the channel-billed toucan (Ramphastos vitellinus).

Habitat

Most toucans are canopy specialists in tropical or montane rainforest. Secondary vegetation may be inhabited by true toucanets, aracaris, and some of the true toucans. Some of the aracaris and the toco toucan are riverine specialists, and species such as red-breasted (Ramphastos dicolorus) and toco toucans may inhabit palm savanna.

Behavior

Toucans wander through the forests and adjacent clearings in small family groups and flocks; such flocks rarely consist of more than twelve birds. Toucans are not intensely sociable; they never take flight in a tight group, but instead wander about in loose groups. The agile aracaris fly swiftly and in a straight line; large toucans are poor fliers. After beating their wings a few times, they hold them out and glide downward, as if pulled down by the weight of their large bills. Then they begin to beat their wings again. The flight, as a result, is both undulating and brief.

Toucans preen one another, particularly on the head and nape, with the tip of the bill. When sleeping, toucans lay the bill up over the back, and tip up the tail, forming a roof over the back and bill. One can see how advantageous such a "feather ball" is to the aracaris, which sometimes sleep five or six together in an old woodpecker tree hole or in rotted hollow tree trunks; the last bird to squeeze in enters the hole backwards, with its tail laid over its back.

Toucans utter melodious calls many times in the late afternoon, continuing when most other birds have gone to rest, but are inactive at night. They also vocalize more during morning hours, and after rains. They prefer to remain high in trees, even bathing in the rainwater pools that form in the fork of a tree or on a thick horizontal branch.

Although many species have ranges that overlap, D. Brooks found that species living in the same region have bills of different lengths and take different prey, thus avoiding competition. The only case of competitive exclusion where two similar-sized species coexist involves pale-billed aracaris (Pteroglossus flavirostris), a species that is restricted to the forest canopy in the Peruvian Amazon by chestnut-eared aracaris (Pteroglossus castanotis), which occupy forest edge almost exclusively. Competitive exclusion is assumed because pale-billed aracaris in Venezuela will use edge forest, not just forest canopy, in the absence of chestnut-eared aracaris; meanwhile chestnut-eared aracaris in Paraguay, where there are no pale-billed aracaris, remain in forest-edge habitat.

Most toucan species are year-round residents in their home range but montane species may undergo seasonal altitudinal migrations, moving downslope in fall and upslope in spring. For some lowland species there are records of huge flocks invading areas with fruiting trees after the breeding season, when fruits become scarce.

Feeding ecology and diet

All toucans forage in the forest canopy (as opposed to the understory or on the ground). Fruits (and some flowers) are a toucan's primary food. Fruits eaten include those of palms (such as Mauritia, Euterpe, Oenocarpus), nutmeg (Virola), figs (Ficus), guava (Psidium), red pepper (Capsicum fructescens), and other fruits such as Casearia corymbosa, Cecropia, Didymopanax, Phytolacca, Rapanea, and Ehretia tinifolia. Although most of the toucan diet is composed of fruit, these birds occasionally eat small mammals such as bats, plus baby birds and bird eggs. They also eat insects such as crickets, cicadas, spiders, and termites, other small invertebrates, and lizards and snakes. Toucans often drink water from epiphytic bromeliads rather than descend to the ground to drink from a pool or stream. Toucans that plunder nests to eat eggs and chicks are often mobbed by the other birds.

Though specialization on fruit may decrease with increasing body size, toucans as a group are primarily frugivorous. Remsen and his colleagues found fruit in 96.5% of all toucan stomachs they examined. Arthropod prey was found in only 5.5% of stomachs, and vertebrate prey was found in fewer than 1% of samples.

Toucans pluck fruit while perched. Getting a small berry from the tip of the huge bill into the throat is quite a task; toucans perform it by jerking the head back while the bill is open. Large lumps of food are held under the foot and reduced to smaller lumps with the bill. When the soft part of a berry has been digested, large seeds are regurgitated on the spot; smaller seeds pass through the digestive tract and are dispersed. This seed dispersal helps to regenerate the tropical forests where toucans live.

Reproductive biology

Typically the male feeds berries to the female as part of courtship. Mutual preening is also an important aspect of courtship. Toucans form monogamous pairs.

Eggs are ellipitical and white. The clutch typically ranges from two to four eggs, though as many as six may be laid in some species. The egg may be as heavy as 5% of the weight of the female in some species. Incubation lasts approximately 18 days, but this depends on the species. Both parents incubate.

Toucans nest in tree holes, usually high above the ground; the larger species prefer natural cavities in rotted trees, while the smaller ones often use woodpecker holes. Chestnut-eared aracaris will nest in abandoned tree-termite nests. Toucans

sometimes drive woodpeckers away from newly excavated nest holes, and then enlarge the entrance if it is too narrow for them. The floor of the hole is typically 3–8 in (8–20 cm) below the opening. Toucans sometimes lay their eggs in the same hole year after year. The eggs lie on wood debris, or often on a lining of seed pellets that the birds have regurgitated before egg laying.

Newly hatched toucans have bare red skin that is not covered with down. Their bills are short, with the lower bill longer and wider than the top, as is the case with young woodpeckers. Thick, horny swellings on the heels protect these joints from friction. The heel pads have sharp outgrowths that may form a ring; these "tarsal calluses" fall off after the young leave the nest.

Both parents brood the naked nestlings, and parents also share the work of feeding their young. They bring some of the food in the tips of the bill, but most food is carried in the throat or esophagus and regurgitated at the nest. Parents and older nestlings clean the nest hole and carry refuse away in their bills. Young toucans open their eyes after they are three weeks old. Their feathers grow so slowly that young still show much bare skin even after they are a month old. Young of the largest species probably remain in the nest for about 50 days. Fledglings typically begin feeding themselves 8–10 days after leaving the nest.

Conservation status

The main enemies of adult toucans seem to be raptors, which sometimes catch toucans almost as large as themselves. Of the 41 toucan species, only the yellow-browed toucanet (Aulacorhynchus huallagae) is considered Endangered. The main threat to this Peruvian species is loss of habitat.

Three additional species are considered Near Threatened, however. The saffron toucanet (Baillonius bailloni) of central South America is threatened by habitat destruction, capture for the cage bird industry, and hunting to some degree. Two of the mountain toucans—the plate-billed (Andigena laminirostris) and gray-breasted (Andigena hypoglauca)—are threatened by habitat destruction in the Andes, where they are endemic.

Significance to humans

A Brazilian folk tale relates that the toucan wanted to be ruler of all birds, so it hid inside a tree cavity with only its large bill visible through the hole. Seeing the massive bill, the other birds accepted the toucan as king—until it emerged from the cavity. Then the thrush noted that despite its large bill, the toucan had a small body, and the toucan was humiliated by all birds.

Amazonian Indians use colorful toucan feathers and bills for decoration, especially those of true toucans (Ramphastos) and aracaris (Pteroglossus). In some cultures toucan flesh is relished, and the birds are regarded as trophies of sorts.

Native South Americans sometimes take young toucans from their nests and keep them as free-flying pets. The first European settlers in South America often kept pet toucans as well. Such tame toucans have been known to dominate chickens in villages and farmyards.

Species accounts

List of Species

Chestnut-eared aracari
Yellow-browed toucanet
Saffron toucanet
Plate-billed mountain toucan
Gray-breasted mountain toucan
White-throated toucan
Toco toucan

Chestnut-eared aracari

Pteroglossus castanotis

taxonomy

Pteroglossus castanotis Linnaeus, 1758. This genus falls between green toucanets (Aulacorhynchus) and black toucanets (Selenidera).

other common names

French: Aracari à oreillons roux; German: Braunohr-Arassari; Spanish: Arasari Orejicastano.

physical characteristics

The smallest and most slender of the toucans; compared to others in the genus, this species is comparatively large and heavy bodied. Length about 18 in (46 cm); average weight 8.7–9.7 oz (247–275 g) males; 8.5–9.5 oz (240–271 g) females. This species is named for the chestnut "ear" patches on its black head. Plumage is typical of this genus, with a dark-green back and yellow underparts; the species is distinguished from close relatives by the single red band across its yellow belly. Bill is dark-brown to black with a yellow streak extending to the tip of the upper mandible and distinct, ivory-colored "teeth." Eye is usually white but sometimes straw yellow; skin around the eyes is blue.

distribution

The most widely distributed aracari, found throughout the tropics of South America, from the Colombian Amazon

through eastern Ecuador, Peru, and Boliva, western Brazil, and eastern Paraguay to northeastern Argentina.

habitat

This species occurs in moist lowland tropical rainforest, up to 2,950 ft (900 m) elevation, often in swamp forests or along lake and river edges; it is the most common aracari on river islands. Unlike most other toucan species, often found in open forest habitat and even gardens around homes; commonly seen at forest edges and roadsides.

behavior

Hilty and Brown describe the call as "a sharp, inflected skeezup." Often seen in pairs but birds also forage in small family groups of three to five. Individuals roost nightly in woodpecker holes, sometimes evicting the official occupant.

feeding ecology and diet

Mainly eat fruit of Cecropia, Ocotea, Ficus, and Coussapoa; will hang upside down to reach fruit. Occasionally take insects and have been documented raiding nests of yellow-rumped caciques (Cacicus cela) among others. Sometimes forage in mixed flocks with other toucan species.

reproductive biology

Not well known. This species nests both in tree holes and in abandoned arboreal termitaria.

conservation status

Not threatened.

significance to humans

Sometimes hunted for meat.


Yellow-browed toucanet

Aulacorhynchus huallagae

taxonomy

Aulacorhynchus huallagae Carriker, 1933. This species shares the genus Aulacorhynchus with six other species of toucanets.

other common names

French: Toucanet à sourcils jaunes; German: Gelbbrauen-Arassari; Spanish: Tucancito de Cuello Dorado.

physical characteristics

Like other members of this genus, has a green back; underparts are red with golden-yellow undertail coverts and white band around base of tail. Length 14–16 in (37–41 cm); weight 9.3 oz (264 g) male; 9.8 oz (278 g) female.

distribution

This species is restricted to two small and isolated highland forest fragments in central Peru.

habitat

This species occupies the canopy of cool, humid, cloud-forests from 6,970–8,240 ft (2,125–2,510 m) in elevation, where trees are thickly covered with epiphytes and undergrowth is dense.

behavior

Not well known. Calls are low-pitched and frog-like.

feeding ecology and diet

Not well known; has been seen feeding on flowers and melas-tome (family Melastomataceae) fruits. Remsen et al. examined stomach contents of three specimens and found only fruit; no arthropods or small vertebrates.

reproductive biology

Not known.

conservation status

Endangered. Habitat loss due to widespread deforestation is the principal threat. The geographic range is estimated at 175 mi2 (450 km2). Although this species occurs within the Rio Abiseo National Park, the population may be small. Precise numbers are unknown, but populations appear to be declining.

significance to humans

None known.


Saffron toucanet

Baillonius bailloni

other common names

French: Toucan de baillon; German: Goldtukan; Spanish: Tucán Amarillo.

taxonomy

Baillonius bailloni Vieillot, 1819. The saffron toucanet is the

sole representative of the genus Baillonius, which is the only monotypic ramphastid genus. Peters (1934–1986) groups this species with the genus Andigena.

physical characteristics

A medium-sized toucanet, about 10 in (35 cm) long. Average weight 5.7 oz (163 g). In the field, the only toucanet to appear mostly yellow; bill is red and green. Eye is yellow and surrounded by red skin.

distribution

This species is limited to the south Atlantic forests of eastern Paraguay, southestern Brazil, and northeastern Argentina.

habitat

Not well known. This species ranges from lowland tropical evergreen forest up to 5,100 ft (1,550 m) in lower montane forest.

behavior

Calls are similar to those of aracaris Pteroglossus. Described as silent and secretive in its habits.

feeding ecology and diet

Has been seen eating figs, palmito fruits, and Cecropia fruits, but feeding ecology not well known. Captive birds hold fruits with feet while breaking into smaller pieces. Remsen et al. examined stomach contents of five specimens and found only fruit, no arthropods or small vertebrates.

reproductive biology

Little is known. Courtship feeding and allopreening occur. Nests in tree cavities; male and female sometimes drum like woodpeckers near the nest entrance.

conservation status

Near Threatened due to habitat loss, capture for the cage bird industry, and to some degree hunting. Habitat destruction is mostly a consequence of agrarian conversion.

significance to humans

Sometimes hunted for meat.


Plate-billed mountain toucan

Andigena laminirostris

taxonomy

Andigena laminirostris Gould, 1850. This species shares the genus Andigena with three other species of mountain toucans. The group appears to be a "link" between the saffron toucanet (Baillonius) and true toucans (Ramphastos).

other common names

French: Toucan montagnard; German: Leistenschnabel-tukan; Spanish: Tucán Andino Piquilaminado.

physical characteristics

Length about 20 in (51 cm). Weight 11.1 oz (316 g) male; 10.7 oz (305 g) female. A dark olive-brown bird with slate-blue underparts; the dark bill has a raised, rectangular, cream-colored plate near the base; skin surrounding the eye is blue above and yellow below.

distribution

Comparatively small range, restricted to a band on the west slope of the Andes from southwestern Colombia through western

Ecuador. Thought to undergo seasonal altitudinal migration in Colombia.

habitat

This species occupies humid montane rainforest where bromeliads and mosses are abundant. Although usually found at 3,900–10,500 ft (1,200–3,200 m), seasonal altitudinal migration occurs and birds may be found as low as 990 ft (300 m).

behavior

Call (equivalent of song) is nasal, whining sound that rises with each note. Often seen foraging in pairs or small groups, and sometimes accompanies mixed-species flocks. Larger flocks of a dozen or more birds form in the fall, after nestlings fledge; at this time birds in Colombia may migrate downslope in search of food.

feeding ecology and diet

Adult birds forage in small groups of three to six, usually up in the forest canopy; daily movements of small flocks vary depending on location of ripe fruit. At least 49 plant species produce fruits eaten by this toucan; most are in the Cecropia family and most are swallowed whole. Remsen et al. examined stomach contents of eight specimens and found only fruit; no arthropods or small vertebrates; however nestlings are fed beetles as well as birds' eggs, snails, and mice along with fruit.

reproductive biology

Breeding season peaks in June and July, when the weather is driest and fruit is most abundant. When a pair of toucans is ready to begin nesting, they drive away the other members of the small group with which they usually forage. Nesting pairs also sometimes evict toucan-barbets from active nests to get control of a tree cavity. The cavities selected are often in trees in the familiy Laureaceae; birds are thought to do some excavation to modify the cavity and entrance hole. Courtshipfeeding occurs before copulation. Both male and female incubate the eggs and feed the young. The nestlings fledge 46–60 days after hatching but the parents continue to feed them for two or three weeks; a second clutch sometimes follows.

conservation status

Near Threatened due to habit loss from intensive logging, human settlement, cattle grazing, mining, and palm cultivation. Large tracts of suitable habitat do remain, however with some areas already protected. The species may be threatened to a lesser extent by the international cage bird trade.

significance to humans

A desired sighting for bird watchers.


Gray-breasted mountain toucan

Andigena hypoglauca

taxonomy

Andigena hypoglauca Gould, 1833. This species shares the genus Andigena with three other species of mountain toucans.

other common names

French: Toucan bleu; German: Blautukan; Spanish: Tucán Andino Pechigris.

physical characteristics

Length about 18 in (46 cm). Weight 12 oz (341 g) male; 10 oz (287 g) female. Head is black, contrasting with pale gray collar

on nape and blue skin around eyes. Chest slaty blue; back and wings bronze-green; tail is black with red undertail-coverts. Distinctive multi-colored bill is red and black at the tip and yellow-green at the base, with two black, oval "thumbprints," one on each side of the lower bill.

distribution

This species is restricted to the west slope of the central Andes, from central Colombia through Ecuador to southeast Peru. Usually occurs at higher elevations than all other mountain toucans.

habitat

Occupies montane rainforest and elfin forest from 5,900–11,300 ft (1,800–3,450 m), but typically not lower than 7,800 ft (2,400 m), where trees are draped with moss and other epiphytes.

behavior

An uncommon and secretive bird; habits are not well known. Typically stays high in the canopy. The call is a series of nasal rising pitches, repeated over and over at four- to five-second intervals.

feeding ecology and diet

Not well known; Remsen et al. examined stomach contents of 14 specimens and found only fruit, particularly those of Cecropia and blackberries; no arthropods or small vertebrates. Feeds quietly, sometimes hanging upside down to reach fruits, usually foraging alone or in pairs but sometimes in small, possibly family, groups.

reproductive biology

Not much known; adults with offspring have not been reported by scientific observers. Males in breeding condition have been collected in late January and early February.

conservation status

Near Threatened due to rapid deforestation resulting from intensive agrarian expansion, logging, and mining. The species may also be threatened to a lesser extent by the international cage bird trade.

significance to humans

A desired sighting for bird watchers.


White-throated toucan

Ramphastos tucanus

taxonomy

Ramphastos tucanus Linnaeus, 1758. The genus Ramphastos is made up of 11 species, the largest members of the toucan family. The clade is most closely allied to the mountain toucans (Andigena).

other common names

English: Red-billed toucan, Cuvier's toucan; French: Toucan de Cuvier; German: Weissbrusttukan; Spanish: Tucan Goliblanco.

physical characteristics

Length about 24 in (55 cm); weight about 21.8–24.8 oz (618–702 g) male; 19.4–24.2 oz (551–687 g) female. A large bird, jet-black from the top of the head down the nape and back to the rump. White at the throat, as the name indicates, with narrow red breast band; below that, black belly and thighs. Yellow uppertail-coverts and red undertail-coverts set off the black tail. The ring of bare skin around the eye is blue; the bill is mostly red (subspecies tucanus) or black (subspecies

cuvieri) with a narrow yellow stripe along keel of upper bill; base of bill is yellow on top and blue on bottom.

distribution

Primarily Amazonian in distribution, ranging from Colombia and eastern Venezuela through Bolivia and Brazil. Often occurs in the same areas as the similar-looking (though smaller) channel-billed toucan.

habitat

Occupies tropical lowland Amazonian forest almost exclusively, ranging up to 3,600 ft (1,100 m). Also seen in second-growth forest, edge habitat and clearings, and around towns and cities.

behavior

A conspicuous, large toucan that typically perches on dead branches above the forest canopy. The yelping call—considered the characteristic bird call of the Amazon—is said to resemble a puppy's barking; it begins with a sharp, descending, whining note that is followed by two to four additional monosyllabic pitches. Birds usually travel in pairs or small family groups of up to six birds, although larger flocks are sometimes seen. Aggressive and dominant in interactions with other species at fruit trees. Flockmates seem to engage in play, including bill-fencing, tag, and pass-the-fruit.

feeding ecology and diet

Not well known but eats a variety of fruits plus insects and lizards and takes eggs and nestlings from a variety of passerines. An active bird when feeding, often plucks fruit with tip of bill, then tosses head so fruit falls backward into mouth. Wipes bill on tree branch afterward, or scrapes bill with foot. To drink, turns bill sideways and swipes across surface of water, then lifts bill up and tilts head back.

reproductive biology

Courtship behaviors include bill-nibbling, allopreening, and courtship feeding. The breeding season varies with location. Nests are constructed in natural tree cavities, 3–60 ft (1–18 m) off the ground; birds often re-use cavities where they have nested successfully in the past. The two to three white eggs are elliptical in shape; the parents share incubation duties and the eggs hatch after about 15 days. Both parents feed the young, which open their eyes after 29 days and fledge after about 49 days. Capuchin monkeys are a threat to toucan eggs and young.

conservation status

Not threatened.

significance to humans

Hunted by Native Americans for food.


Toco toucan

Ramphastos toco

taxonomy

Ramphastos toco Mueller, P.L.S., 1776. The genus Ramphastos includes the largest members of the toucan family. The clade is closest allied to the mountain toucans (Andigena).

other common names

French: Toucan toco; German: Riesentukan; Spanish: Tucán Toco.

physical characteristics

The largest of all toucans. Length about 24 in (60 cm). Weight 26.8 oz (760 g) male; 20.7 oz (587 g) female. The only Ramphastos species with a predominately black-and-white body (other species in this group may have orange, orange-red, or yellow on the breast or throat). Enormous orange bill with black spot at the tip is unmistakable.

distribution

This species ranges from the mouth of the Amazon River southward to southern Brazil and northern Argentina.

habitat

This species inhabits more macrohabitats than any other toucan and is the species most likely to be seen in open and semi-open habitat. For example, it may be found in tropical forest, Chiquitano forest, pantanal, seasonal inundated savanna, and secondary vegetation. A lowland species, the toco toucan ranges up to 3,900 ft (1,200 m) in altitude.

behavior

Of all the toucans, this is the species most likely to be seen in flight over rivers and across open areas; often perches high in trees, on dead branches. Flap-glide flight is slow and undulating. The call is perhaps the lowest in pitch of all toucans; has been compared to snoring or the croaking of a toad. Often rattles bill or raps tongue against closed bill.

feeding ecology and diet

May feed alone, with a mate, or in a small flock of up to nine birds. Very agile and often hangs head down to reach a fruit or probe a crevice. Typically feeds in the canopy, but unusual among toucans in sometimes alighting on the ground to take fallen fruits. Eats a variety of fruits plus arthropods and has been seen hunting cooperatively for eggs and nestlings in nesting colonies of yellow-rumped caciques.

reproductive biology

Thought not to breed until they are two years old. Pairs engage in mutual preening and bill-fencing. Often nest in palm tree cavities which they modify by excavating with their sturdy bills; also nest in burrows in earthen banks, and in tree-termite nests (after nests have been opened by woodpeckers). The male and female incubate the two to four white eggs for about 18 days; nestlings are feed insects initially, then diet becomes mostly fruit. Young birds fledge at 43 to 52 days.

conservation status

Not threatened. May be expanding its range into newly cleared areas in Amazonia.

significance to humans

A flagship species of the Neotropics, this toucan is often depicted in South American art. Still hunted for food throughout most of its range; young birds often taken for pets.


Resources

Books

Birdlife International. Threatened Birds of the World. Barcelona: Lynx Edicions, 2000.

Brooks, D.M. "¿Son la competencia, el tamaño y la superposición de dietas pronosticadores de la composición de Ramphastidae?" In Manejo de Fauna Silvestre en la Amazonia, edited by T.G. Fang et al., pp. 283–288. Bolivia: United Nations Development Program, 1997.

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

Ridgely, R.S., and P.J. Greenfield. The Birds of Ecuador. Vol. 1, Status, Distribution, and Taxonomy. Ithaca: Cornell University Press, 2001.

Short, L.L., and J.F.M. Horner. Toucans, Barbets, and Honeyguides. New York: Oxford University Press, 2001.

Sibley, C.G., and J.E. Ahlquist. Phylogeny and Classification of Birds: A Study in Molecular Evolution. New Haven, CT: Yale University Press, 1993.

Sick, Helmut. Birds in Brazil: A Natural History. New Jersey: Princeton University Press, 1993.

Stotz, Douglas F., et al. Neotropical Birds: Ecology and Conservation. Chicago: University of Chicago Press, 1996.

Periodicals

Buhler, P. "Size, Form and Coloration of the Ramphastid Bill as Basis of the Evolutionary Success of the Toucans?" Journal of Ornithology 136 (1995): 187–193.

Haffer, J. "Avian Speciation in Tropical South America." Publication of the Nuttall Ornithology Club 14 (1974).

Remsen, James V., et al. "The Diets of Neotropical Togons, Motmots, Barbets, and Toucans." Condor 95 (1993): 178–192.

Organizations

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

Cynthia Ann Berger, MS

Daniel M. Brooks, PhD