Keel-billed toucan

Including its bill, the length of the keel-billed toucan ranges from around 42 to 55 cm (17 to 22 in).^[5] Its large and colorful bill averages around 12–15 cm (4.7–5.9 in), about one-third of its length. The wingspan of the keel-billed toucan typically ranges from 189.4 to 208.4 mm^[6]. It typically weighs about 380–500 g (13–18 oz).^[7] While the bill seems large and cumbersome, it is in fact a spongy, hollow bone covered in keratin, a very light and hard protein.^[8]

The plumage of the keel-billed toucan is mainly black with a yellow neck and chest. Molting occurs once per year.^[4] It has blue feet and red feathers at the tip of its tail. The bill is mainly green with a red tip and orange sides.

Keel-billed toucans have zygodactyl feet (or feet with toes 2 and 3 facing forwards, and toes 1 and 4 facing backwards) – two toes face forward and two face back. Because toucans spend a large portion of time in the trees, this helps the birds to stay on the branches of the trees and jump from one branch to another.

Other than size, males and females of the species look similar.^[9]

The keel-billed toucan can be found from Southern Mexico to Venezuela and Colombia. It roosts in the canopies of tropical, subtropical, and lowland rainforests, up to altitudes of 1,900 m (6,200 ft).^[13] It roosts in holes in trees,^[4] often with several other toucans. This can be very cramped, so the birds tuck their tails and beaks under their bodies to keep their body temperature at a normal level while sleeping. Adding to the lack of space, the bottoms of the holes are often covered with pits from the fruit the toucans have eaten.^[4]

Like many other toucans, keel-billed toucans are very social birds and are rarely seen alone. They fly in small flocks of approximately six to twelve individuals through lowland rainforests. Their flight is slow and undulating, consisting of rapid wing beats (six to ten), then a glide with the bird's beak extending forward and dipping downward as though pulling the rest of the bird.^[4] Their feet are drawn up forward in flight. The flight distances are typically short.^[4]

They live together in groups, often sharing cramped living quarters of holes in trees, where 5 or 6 birds could fit into a single hole together.^[14] The birds look for holes around 20 feet off the ground, with smaller holes for an entrance. In order to fit in these small holes, the birds fold their tail over their body and tuck the large beak along their backs. ^[15] There is a family structure within the group. Birds often "duel" with each other using their bills, and throw fruit into each other's mouths. They 'play ball', one throwing a fruit in the air and a second seizing it.^[4]

Vocalizations by the birds include sounds like “grr”, “trrii” and “rrrk.” A louder male could be heard over half a mile away. They also communicate with non-vocal noises by clacking their large beaks and beating their wings. ^[16]

The keel-billed toucan is sometimes kept in captivity, but it requires a high-fruit diet and is sensitive to hemochromatosis, an iron storage disease.^[25]

The keel-billed toucan is threatened by habitat loss, which has been accelerating in recent years, and by hunting and trapping for the wildlife trade. The species is undergoing a moderately rapid population decline and is therefore categorized as a near-threatened species.^[1] The decline rate in 2021 of the past 3 generations was estimated to be from 10–19%, although future populations were estimated at a higher 20–29%.^{[citation needed]}