Citron-throated Toucan

## About

A citron-throated toucan perching on a tree branch, holding a berry in it's bill.

## Classification

### Subspecies

R. v. citreolaemus
(formerly R. citreolaemus)

The citron-throated toucan ***(Ramphastos vitellinus citreolaemus)***, is a subspecies of the channel-billed toucan ***(Ramphastos vitellinus)***. The subspecies is named for the lemon yellow colour that fades into a citrus orange at the lower part of the bird's bib-patch. The bib-patch itself is mostly white, with a red breast band bordering the bottom and blue feathers framing the bird's eyes. The bare skin around the eyes is also blue. Citron-throated toucans have black bills that have the characteristic groove, or 'channel' shared by its relatives. The bill is black however, a band of bluish-green runs longitudinally across the bird's bill and similar colours the base of the bill, accompanied by more orange colours. The plumage of the citron-throated toucan is the same as other toucans, being jet black across its body, apart from the red and yellow feathers above and below the bird's rump. All toucan species have characteristic zygodactyl feet, defined by two toes on both the front and back of the feet. The purpose of the toucan's bill has long been debated however, the conclusion most often reached by ornithologists, is that the bill is used for greater temperature regulation. Blood-flow is greatly controlled to the area, in an efficient way, in order to cool the bird down in the humid rainforest environments it inhabits. The bill can grow to a length of 14cm (5.5in). The taxonomic situation of the citron-throated toucan in particular is more debated than the other channel-billed subspecies, with some modernly encouraging the placement of the animal as its own species, while others continue to label the bird as a subspecies. Some have also began to believe that the citron-throated toucan should be classed as a subspecies of the white-throated toucan ***(Ramphastos tucanus)***, due to the two having morphological similarities. Citron-throated toucans can grow to a length of 48-56cm (19-22in), making it one of the larger toucans. The bird weighs around 450g (15oz).

## Diet

Toucans are omnivorous birds however, most species prefer to eat various species of fruit over meat. The citron-throated toucan consume a variety of insects and arthropods, but may also feed on larger prey such as amphibians and eggs. Toucans eat by tossing food into the air and then catching it at the back off their throats rather than just chewing. This method of feeding is due to the lack of dexterity in the bird's bill.

## Conservation Status

There are currently no threats listed on the citron-throated toucan's IUCN page however, the bird likely suffers from habitat-loss, as do most rainforest species.

## Range and Population

Citron-throated toucans occur in the northern and northwest reaches of Colombia and Venezuela respectively. Here, they inhabit; dense lowland tropical forests, rainforests and cloud forests, with an upper elevation limit of 1,700m (5,577ft). Despite their usual reliance on forest habitats, citron-throated toucans can also be found on the outskirts of these environments, in places like tropical savannas. No matter which environment they inhabit however, they are always in close proximity with water sources such as inland wetlands. Though the population of the citron-throated toucan is unknown, it is believed to be nearing the thresh-hold to being considered vulnerable (>10,000 individuals) and is decreasing. The decreasing state of the population is not thought to be readily approaching vulnerable status however, the subspecies' population is thought to have decreased by >10% in the last 3 generations (2022 analysis).

## Behaviour

Citron-throated toucans are social birds that travel in groups, constantly communicating to each other loudly. Citron-throated toucans are known as 'croaking' toucans, as their calls mirror those of frogs. During courtship, citron-throated toucans will toss fruit at one another, attempting to catch each other's gifts. The pair will also allopreen one another and vocalise. The female will lay 2-4 eggs in a pre-excavated tree cavity and both parents will contribute in incubation until the chicks hatch after 16-18 days. The nestlings are altricial, being completely dependent on their parents for their survival and are born blind and featherless however, after 3-4 weeks the eyes will begin to open and feathers begin expanding. After the transformation, the young will stay with their parents for a subsequent 6-8 weeks, whilst their fledging occurs and their bills grow.

### Relationship with Humans

Toucan species in general have always been regarded as important and valued animals in Amazonian culture. The Amazonian peoples believe that the birds represent both the living and spirit worlds. In more western cultures, citron-throated toucans are often kept as exotic pets in household environments.

## In Captivity

Other than being kept as an exotic pet, the citron-throated toucan is unpopular in captivity. It can be found at the Dallas World Aquarium, an aquarium that specialises in showcasing the aquatic and terrestrial wildlife of predominantly rainforest environments.

## Sources

* IUCN Red List of Threatened Species - https://www.iucnredlist.org/species/62220237/95192753
* Citron-Throated Toucan | Birdlife International Datazone - http://datazone.birdlife.org/species/factsheet/citron-throated-toucan-ramphastos-citreolaemus
* Citron-Throated Toucan | The Dallas World Aquarium - https://dwazoo.com/animal/citron-throated-toucan/