Toco toucans (Ramphastos toco) thrive over a wide range of habitats and locations throughout much of the Neotropical region. They are native to the countries of Argentina, Peru, French Guiana, Bolivia, Paraguay, Suriname, and Brazil. Studies have shown a correlation between the wide range of R. toco and the availability of fleshy fruits, which make up the majority of the toucan's diet.
Biogeographic Regions: neotropical (Native )
- BirdLife International, 2009. "IUCN red list of threatened species" (On-line). Accessed February 11, 2010 at http://www.iucnredlist.org/apps/redlist/details/141926/0.
- Ragusa-Netto, J. 2006. Abundance and frugivory of the toco toucan (Ramphastos toco) in a gallery forset in Brazil's Southern Pantanal. Brazilian Journal of Biology, 66: 133-142.
- Ragusa-Netto, J. 2008. Toco toucan feeding ecology and local abundance in a habitat mosaic in the Brazilian cerrado. Ornithologia Neotropical, 19: 345-359.
Toco toucans are recognized as the largest species in the toucan family and flaunt the biggest beak in regard to body size of all birds. This large yellow-orange colored beak with a distinct black marking at the tip of the bill is the most noticeable feature of R. toco. It accounts for one-twentieth of the total mass of the toucan, while also contributing to one-third of the bird's total length. Toco toucans weigh between 592 and 760 g, and average 61 cm in length. This species has what appears to be a blue iris, but is in fact a thin layer of skin that surrounds the eye. The blue circle is encompassed by an additional ring of orange skin that adds to the colorful physical appearance of toco toucans. Its basal metabolic rate is estimated at 8.72 cubed cm of oxygen per hour. Sexual dimorphism is present in this species of toucan. Measurements and observations reveal physical differences between males and females. Adult male toco toucans are typically larger than adult females. Juveniles are easily differentiated from the adults due to the young's duller colors and stubbier bill.
Range mass: 592 to 760 g.
Average length: 61 cm.
Average basal metabolic rate: 8.72 cm3.O2/g/hr.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
- Castro, M., S. Recco-Pimentel, G. Rocha. 2003. Sexual dimorphism in Ramphastos toco and Ramphostos dicolorus (Piciformes, Aves). Revista de Biologia Tropical, 51: 241-245.
- McNab, B. 2009. Ecological factors affect the level and scaling of avian BMR. Comparative Biochemisty and Physiology, 152: 22-45.
- Seki, Y., M. Schneider, M. Meyers. 2005. Structure and mechanical behavior of a toucan beak. Acta Materialia, 53: 5281-5296.
- Tattersall, G., D. Andrade, A. Abe. 2009. Heat exchange from the toucan bill reveals a controllable cascular thermal radiator. Science, 325: 468-470.
- Zoological Society of San Diego, 2010. "Toco Toucan" (On-line). Accessed February 12, 2010 at http://www.sandiegozoo.org/animalbytes/t-toucan.html.
Toco toucans are most commonly found in dry semi-open areas, which include regions such as woodland, savanna, plantations, and other regions that consist of scattered trees. In Brazil, toco toucans have been found in abundance in the "cerrado." Brazil's cerrado consists of savanna, semidecidious, and gallery forests surrounding river corridors. They are canopy frugivores that rely heavily on the availability of seasonal fruiting plants. Toco toucans therefore move from one habitat and region to the next in order to satisfy their dietary needs. This species is typically found at lowland elevations. However they have been sighted in elevations up to 1750 m around the Andes mountain range of South America.
Range elevation: 1750 (high) m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest ; scrub forest
Other Habitat Features: riparian
- Absolute Astronomy Contributors, 2009. "Toco Toucan" (On-line). Accessed February 12, 2010 at http://www.absoluteastronomy.com/topics/Toco_Toucan.
Habitat and Ecology
Toco toucans are canopy frugivores whose diet is composed mainly of fruits, but they are considered to be an opportunistic feeder. They also occasionally feed on various types of insects and eggs of other birds, including those of endangered hyacinth macaws (Anodorhynchus hyacinthinus). Their broad geographical range of habitats is due in part to their foraging behavior and their diet of briefly-available fruits. The food sources include the fruits from trees such as genipapo (Genipa americana), agarrapolo (Ficus luschnathiana), ambay pumpwood (Cecropia pachystachya).
The large bills of toco toucans are the main foraging tool that allows the birds to reach into tree holes and to grasp fruits from surrounding branches. Toco toucans are unique in that they does not use their tongue in the process of swallowing food. Instead, they place a piece of fruit between the very end of their beak and lean their head back at an approximately 180 degree angle. This causes the food item to project directly into the pharynx.
Animal Foods: amphibians; reptiles; eggs; insects
Plant Foods: seeds, grains, and nuts; fruit
Primary Diet: herbivore (Frugivore )
- Baussart, S. 2007. Feeding mechanism in fruit-eating bird toucan, Ramphastos toco. Comparative Biochemisty and Physiology, 146: S107.
Even though toco toucans prey on the eggs of endangered hyacinth macaws (Anodorhynchus hyacinthinus), these macaws are in fact indirectly dependent on the toucans. Since hyacinth macaws almost always nest in the hollows of the manduvi tree and the manduvi tree depends upon the seed dispersal services provided by toco toucans, hyacinth macaws are indirectly dependent on this species of toucan.
Ecosystem Impact: disperses seeds
Although the colorful characteristics of toco toucans provide adequate camouflage in the forest canopy, common predators include jaguars (Panthera onca), snakes (order Serpentes), coatis (Nasua and Nasuella species), and eagles (Accipitridae).
- Jaguars (Panthera onca)
- Snakes (order Serpentes)
- Coatis (Nasua and Nasuella species)
- Eagles (Accipitridae)
Anti-predator Adaptations: cryptic
- New World Encyclopedia Contributors, 2008. "Toucan" (On-line). Accessed February 12, 2010 at http://www.newworldencyclopedia.org/entry/Toucan.
Life History and Behavior
Toco toucans are very loud communicators with various means of sound production. Their repertoire consists of deep, course croaking that is repeated on a consistent basis. A rattling call is also a common form of conversation in this species. Besides vocal communication, they use bill-clacking as a form of auditory communication. Like all birds, toco toucans perceive their environment through visual, auditory, tactile, and chemical stimuli.
Communication Channels: visual ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
A lifespan of 20 years is typically seen in wild toco toucans with a maximum recorded lifespan of 26 years. In captivity, this species of toucan often has a shorter lifespan of approximately 18 years. Toco toucans that have been raised in captivity often experience iron-storage disease, which is sometimes referred to as hemochromatosis. This disease can lead to an uncomfortable life of the toucan involving emaciation, dyspnea, and feather picking and may eventually lead to the death of the bird. Since the diet of toco toucans is primarily fruits, which involves a low intake of iron, they have seemed to develop very iron-absorbent organs. When a toxic amount of iron builds-up within the liver of the bird due to the high-iron diet that many of these captive toucans are fed, the iron-storage disease occurs.
Status: wild: 26 years.
Status: wild: 20 years.
Status: captivity: 18 years.
- Drews, A., S. Redrobe, J. Patterson-Kane. 2004. Successful reduction of hepatocellular hemosiderin content by dietary modification in toco toucans (Ramphastos toco) with iron-storage disease. Journal of Avian Medicine and Surgery, 18: 101-105.
The large colorful bills of toco toucans are often thought to be used in mate choice, but there are no specific studies that lead to this conclusion. However, it is known that this species uses its bill to gather fruit that is used in the bird's mating ritual. This courtship ritual consists of either the male or female initiating a fruit toss with its potential mate. After this ritual has been carried out, the male mates with the female.
Mating System: monogamous
The breeding season for toco toucans occurs in the spring. Tree cavities are the typical nesting site where a single clutch of 2 to 4 eggs are laid by the female. Toco toucans breed yearly and have altricial young. The hatchlings are bare-skinned, close-eyed, and helpless until approximately 6 to 8 weeks later. At this time, the young begin to develop their characteristic beak and will soon fledge. Toco toucans become sexually mature in 3 to 4 years.
Breeding interval: Toco toucans breed once yearly.
Breeding season: The breeding season occurs in the spring.
Range eggs per season: 2 to 4.
Range time to hatching: 15 to 18 days.
Range fledging age: 6 to 8 weeks.
Range age at sexual or reproductive maturity (female): 3 to 4 years.
Range age at sexual or reproductive maturity (male): 3 to 4 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
Both parents take turns incubating the eggs in the small cavity of a tree where the nest is situated. Nests of this species were found to be lined with regurgitated manduvi seeds from the manduvi tree (Sterculia apetala), suggesting that parents may provision nestlings with this fruit. The young remain in the nest for about 6 to 8 weeks.
Parental Investment: altricial ; male parental care ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Male, Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)
- National Geographic Contributors, 2010. "Ramphastos toco" (On-line). Accessed February 11, 2010 at http://animals.nationalgeographic.com/animals/birds/toucan.html.
- Pizo, M., C. Donatti, N. Guedes, M. Galetti. 2008. Conservation puzzle: Endangered hyacinth macaw depeds on its nest predator for reproduction. Biological Coservation, 141: 792-796.
- Zoological Society of San Diego, 2010. "Toco Toucan" (On-line). Accessed February 12, 2010 at http://www.sandiegozoo.org/animalbytes/t-toucan.html.
Evolution and Systematics
Bill of toco toucan acts as a heat exchanger to regulate body temperature by adjusting blood flow
"The toco toucan (Ramphastos toco), the largest member of the toucan family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, from serving as a sexual ornament to being a refined adaptation for feeding. However, it is also a significant surface area for heat exchange. The toco toucan has the remarkable capacity to regulate heat distribution by modifying blood flow, using the bill as a transient thermal radiator. Results indicate that the toucan's bill is, relative to its size, one of the largest thermal windows in the animal kingdom, rivaling elephants’ ears in its ability to radiate body heat." (Tattersall et al. 2009:468)
Sleep-state transitions witnessed as changes in bill temperature. This is a thermal imaging video showing transient changes in bill temperature that occur during sleep while the bill is tucked between the wings. Time-lapsed data obtained at 10-s intervals. Total frames = 724, total length = 2.7 hours. Filmed by the Tattersall Laboratory.
Learn more about this functional adaptation.
- Tattersall, GJ; Andrade, DV; Abe, AS. 2009. Heat exchange from the toucan bill reveals a controllable vascular thermal radiator. Science. 325(5939): 468-470.
Toucan beaks are built lightweight and strong thanks to a rigid foamy inside and layers of fibrous keratin tile outside.
"The Toucan's beak measures one-third the length of the bird but accounts for a mere one twentieth of its weight (Acta Mater. 2005, 53, 5281). Using electron microscopy, the researchers found that the exterior of the beak is made up of overlapping tiles of keratin, the sulfur-containing fibrous protein that makes up hair, fingernails, and horn. The interior of the beak is constructed of a rigid foam made of a network of calcium-rich bony fibers connected by membranes. The membranes are similar in composition to keratin. Meyers was surprised by the beak's ability to absorb high-energy impacts." (no author 2005:26)
"The toucan beak, which comprises one third of the length of the bird and yet only about 1/20th of its mass, has outstanding stiffness. The structure of a Toco toucan (Ramphastos toco) beak was found to be a sandwich composite with an exterior of keratin and a fibrous network of closed cells made of calcium-rich proteins. The keratin layer is comprised of superposed hexagonal scales (50 µm diameter and 1 µm thickness) glued together. Its tensile strength is about 50 MPa and Young’s modulus is 1.4 GPa. Micro and nanoindentation hardness measurements corroborate these values. The keratin shell exhibits a strain-rate sensitivity with a transition from slippage of the scales due to release of the organic glue, at a low strain rate (5 · 10-5/s) to fracture of the scales at a higher strain rate (1.5 · 10-3/s). The closed-cell foam is comprised of fibers having a Young’s modulus twice as high as the keratin shells due to their higher calcium content. The compressive response of the foam was modeled by the Gibson–Ashby constitutive equations for open and closed-cell foam. There is a synergistic effect between foam and shell evidenced by experiments and analysis establishing the separate responses of shell, foam, and foam + shell. The stability analysis developed by Karam and Gibson, assuming an idealized circular cross section, was applied to the beak. It shows that the foam stabilizes the deformation of the beak by providing an elastic foundation which increases its Brazier and buckling load under flexure loading." (Seki et al. 2005:5281)
Learn more about this functional adaptation.
- 2005. Science Concentrates: Secrets of toucan beak revealed. Chem. Eng. News. 83(50):
- Seki Y; Schneider MS; Meyers MA. 2005. Structure and mechanical behavior of a toucan beak. Acta Materialia. 53(20): 5281-5296.
Molecular Biology and Genetics
Barcode data: Ramphastos toco
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Ramphastos toco
Public Records: 2
Specimens with Barcodes: 9
Species With Barcodes: 1
Toco toucans are considered by the IUCN Red List of Threatened Species to be of "least concern." This is due to the broad range and fairly common status of this species in its designated habitats and biogeographic range. They are listed under appendix II of CITES which regulates the trade of this species.
CITES: appendix ii
IUCN Red List of Threatened Species: least concern
UNEP-WCMC, 2009. "
UNEP-WCMC species database: CITES-listed species" (On-line). Accessed March 18, 2010 at http://www.cites.org/eng/resources/species.html.
IUCN Red List Assessment
Red List Category
Red List Criteria
Relevance to Humans and Ecosystems
There are no known adverse effects of toco toucans on humans.
Because of the natural attraction to the colorful and odd bills of toco toucans, tour guides in many South American countries provide trips to see them in their natural habitat. Also, many zoos attempt to preserve the natural beauty of this bird in a safe and people-friendly environment. Toco toucans are also found in the pet trade.
Positive Impacts: pet trade ; ecotourism
The toco toucan (Ramphastos toco), also known as the common toucan or toucan, is the largest and probably the best known species in the toucan family. It is found in semi-open habitats throughout a large part of central and eastern South America. It is a common attraction in zoos.
The toco toucan has a striking plumage with a mainly black body, a white throat, chest and uppertail-coverts, and red undertail-coverts. What appears to be a blue iris is actually thin blue skin around the eye. This blue skin is surrounded by another ring of bare, orange skin. The most noticeable feature, however, is its huge bill, which measures from 15.8 to 23 cm (6.2 to 9.1 in) in length, which is yellow-orange, tending to deeper reddish-orange on its lower sections and culmen, and with a black base and large spot on the tip. It looks heavy, but as in other toucans it is relatively light because the inside largely is hollow. The tongue is nearly as long as the bill and very flat. This species is the largest toucan and the largest representative of the order Piciformes. The total length of the species is 55–65 cm (22–26 in). Body weight in these birds can vary from 500 to 876 g (1.102 to 1.931 lb), with males averaging 723 g (1.594 lb) against the smaller female, which averages 576 g (1.270 lb). Among standard measurements, the wing chord is 22 to 26 cm (8.7 to 10.2 in), the tail is 14.1 to 17.9 cm (5.6 to 7.0 in) and the tarsus is 4.8 to 6.5 cm (1.9 to 2.6 in). Other than the size difference, there is no external differences between the sexes. Juveniles are duller and shorter-billed than adults. Its voice consists of a deep, coarse croaking, often repeated every few seconds. It also has a rattling call and will bill-clack.
It occurs in northern and eastern Bolivia, northern Argentina, eastern and central Paraguay, eastern and southern Brazil (excluding southern Rio Grande do Sul, the dry regions dominated by Caatinga vegetation and coastal regions between Ceará and Rio de Janeiro). Other disjunct populations occur along the lower Amazon River (Ilha de Marajó west approximately to the Madeira River), far northern Brazil in Roraima, and coastal regions of the Guianas. It only penetrates the Amazon in relatively open areas (e.g. along river corridors). It is resident, but local movements may occur.
Habitat and status
It is, unlike the other members of the genus Ramphastos, essentially a non-forest species. It can be found in a wide range of semi-open habitats such as woodland, savanna and other open habitats with scattered trees, Cerrado, plantations, forest-edge, and even wooded gardens. It is mainly a species of lowlands, but occurs up to 1750 m (5750 ft) near the Andes in Bolivia. Because it prefers open habitats it is likely to benefit from the widespread deforestation in tropical South America. It has a large range and except in the outer regions of its range, it typically is fairly common. It is therefore considered to be of Least Concern by BirdLife International. It is easily seen in the Pantanal.
The toco toucan eats fruit (e.g., figs and Passiflora edulis) using its bill to pluck them from trees, but also insects, frogs, small reptiles, small birds and their eggs and nestlings. It also has been known to capture and eat small adult birds in captivity. The long bill is useful for reaching things that otherwise would be out-of-reach. It is also used to skin fruit and scare off predators which include jaguars, snakes, and weasles. It is typically seen in pairs or small groups. In flight it alternates between a burst of rapid flaps with the relatively short, rounded wings, and gliding. They are poor flyers, and usually hop from tree to tree. Nesting is seasonal, but timing differs between regions. The nest is typically placed high in a tree and consists of a cavity, at least part of which is excavated by the parent birds themselves. It has also been recorded nesting in holes in earth-banks and terrestrial termite-nests. Their reproduction cycle is annual. The female usually lays two to four eggs a few days after mating. The eggs are incubated by both sexes and hatch after 17–18 days. These birds are very protective of themselves and their chicks.
The bill of all birds providing 30 to 50% of its body surface area, although another Neotropical species, the sword-billed hummingbird, has a longer bill relative to its body length. It was called by Buffon a “grossly monstrous” appendage. Diverse functions have been suggested. Charles Darwin suggested it was a sexual ornament: “toucans may owe the enormous size of their beaks to sexual selection, for the sake of displaying the diversified and vivid stripes of colour with which these organs are ornamented". Further suggestions have included aid in peeling fruit, intimidating other birds when robbing their nests, social selection related to defense of territory, and as a visual warning.
Research has shown that one function is as a surface area for heat exchange. The bill has the ability to modify blood flow and so regulate heat distribution in the bird, allowing it to use its bill as a thermal radiator. In terms of surface area used for this function, the bill relative to the bird's size is amongst the largest of any animal and has a network of superficial blood vessels supporting the thin horny sheath on the bill made of keratin called the rhamphotheca.
In its capacity to remove body heat the bill is comparable to that of elephant ears. The ability to radiate heat depends upon air speed: if this is low only 25% of the adult bird's resting heat production to as much as four times this heat production. In comparison the bill of a duck and the ears of elephant can shed only 9 to 91% of resting heat production. The bill normally is responsible for 30 to 60% of heat loss. The practice of toco toucans of placing their bills under their wings may serve to insulate the bill and reduce heat loss during sleep. It has been observed that "complexities of the vasculature and controlling mechanisms needed to adjust the blood flow to the bill may not be completely developed until adulthood."
Like the keel-billed toucan, the toco toucan is sometimes kept in captivity, but has a high fruit diet and is sensitive to haemochromatosis (an iron storage disease). Also, pet toco toucans must not be permitted to eat mouse (or rat) meat, due to a risk of bacterial infection. There is an ongoing population management plan that should help to revert the decreasing captive population of the toco toucan for Association of Zoos and Aquariums (AZA) member institutions. This is the second management plan that is occurring since 2001.
- BirdLife International (2012). "Ramphastos toco". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- Toucans, Barbets and Honeyguides (Bird Families of the World) by Lester Short & Jennifer Horne. Oxford University Press (2001), ISBN 978-0198546665.
- Toco Toucan (Ramphastos toco)
- KidsBiology.com - Ramphastos toco
- Tattersall, GJ.Andrade DV. Abe AS. (2009). "Heat Exchange from the Toucan Bill Reveals a Controllable Vascular Thermal Radiator". Science 325: 468–470. doi:10.1126/science.1175553. PMID 19628866.
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- Jones, JS. (1985). "Evolution: The point of a toucan's bill". Nature 315: 182–183. doi:10.1038/315182b0.
- Toco Toucan Birds
- Toco Toucan Population Management plan. Riverbanks Zoo. Accessed 2008-06-28
- Gilbert, A. (2002). Toco Toucan (Ramphastos toco). pp. 270–271 in: del Hoyo, J., Elliott, A. & Sargatal, J. eds (2002). Handbook of Birds of the World. Vol. 7. Jacamars to Woodpeckers. Lynx Edicions, Barcelona. ISBN 84-87334-37-7
- Restall, R., Rodner, C. & Lentino, M. (2006). Birds of Northern South America - An Identification Guide. Christopher Helm, London. ISBN 0-7136-7242-0
- Short, L. & Horne, J. (2001). Toucans, Barbets and Honeyguides. Oxford University Press, London. ISBN 0-19-854666-1
- Sick, H. (1993). Birds of Brazil - A Natural History. Princeton University Press, West Sussex. ISBN 0-691-08569-2