Red-leg tortoise, Savanna tortoise, Jabuti, Marrocoy
The Red-footed tortoise (Chelonoidis carbonarius) is a species of tortoise found in northern South America. It is closely related to the Yellow-footed tortoise from the Amazon Basin. Red-footed tortoises are popularly kept as pets, and over-collection has caused them to be vulnerable to extinction.
Red-footed tortoises show sex, regional, and individual variations in color, shell shape, and minor anatomical characteristics. Adult carapaces are generally an elongated oval with sides that are nearly parallel, although the sides of males may curve inwards. They are fairly highly domed and smooth with a rather flat back (although the scutes may be raised or 'pyramided' in some individuals, especially captive specimens). Often, a high point over the hips is seen, with a small sloped section over the neck. The vertebral and costal scutes (the scutes along the center and sides of the carapace) are black or dark brown with a pale yellow areole in the center. The marginals (scutes along the edge of the carapace) 'tuck under' along the sides and flare slightly over the limbs. They are dark with a pale aureole along the middle of the lower edge. The nuchal scute (the marginal over the neck) is absent, and the marginals over the tail are joined as one large supracaudal. Growth rings are clearly evident in most individuals but become worn smooth with age. The plastron (bottom shell) is large and thick along the edges. The gulars (frontmost pair of plastron scutes) do not protrude much past the front of the carapace. The plastron of a male is deeply indented, and the anal scutes (rearmost pair of plastron scutes) may be used to sex the animal while the color pattern varies by region. Males are usually slightly more colorful than females, and colors vary by region. The head is relatively small with a squared-off profile and flat on top, longer than it is wide. The eye is large with a brown, almost black iris, and rarely any sclera visible around it. The upper jaw is slightly hooked, and the upper jaw is notched in the front middle. About 15 to 20 'teeth' or fine grooves occur on each side of each jaw. The limbs are generally cylindrical with five claws on the fore limbs and four on the hind, but no visible toes. The fore limbs are slightly flattened and the front surface is covered with large scales, mostly with the same color as the head. The tail is muscular, varies in length and overall shape by sex, and lacks any sort of claw on the tip. Hatchling and young Red-footed tortoises have much rounder and flatter carapaces that start off as mostly pale yellow to brown. New growth adds dark rings around the pale center of each scute. The marginals of very young tortoises are serrated, especially over the hind limbs. This probably aids in both camouflage against the leaf litter and in making the small animals harder to eat. Young tortoises are generally more colorful overall.
Red-footed tortoises have a broad range to the east of the Andes from eastern Columbia across the Guianas, south through eastern Brazil as far as Rio de Janeiro, and westwards to Paraguay, Bolivia, and northern Argentina, including Panama and western Columbia and the island of Trinidad. Recently they have been introduced to further islands in the Caribbean. This species occurs in rainforests, temperate forests, dry thorny forests, and savanna areas. They favor heavily forested, humid habitats, avoiding muddy areas due to the difficulty of burrowing in these habitats. They are less commonly found in forest clearings that have mangoes, palms, and other vegetation.
Red-footed tortoises will "gaze follow" members of their own species, which means looking in the same direction as other tortoises in the immediate area. These animals are diurnal and seem to avoid moving far. Most tortoise species are inactive for much of their day, and red-footed tortoises typically spend more than 50% of their daylight hours resting. After a large meal, they may rest even longer, commonly for five to ten days. They seek shelter where there is protection from predators as well as thermoregulation. Shelters are often communal, occupied by as many tortoises as will fill the space. These tortoises make a series of clucks, similar to those made by domestic chickens. The sounds are mainly produced by males at the time of courting or mating. Juveniles also cluck or chirp regularly while foraging. They will pause in their foraging and bob their head as they produce the sound. Not much more is known about the communication or perception of this species.
Red-footed tortoises are omnivores. They eat small quantities of animal matter, including carrion, live or dead plants or fruits, fungi, flowers, soil, sand, and animals that move slowly, such as worms, snails and insects they are able to catch.
Red-footed tortoises are polygynous; males make sounds and calls along with distinct motions of their throat that are for attracting potential mates and warding off competitors. Males fight for mates, bobbing their heads up and down and then wrestling. If he flips the rival onto his back, he gains the opportunity to mate with the female. Courtship peaks during April and May, though breeding occurs throughout the year. Females dig their nest in leaf litter, laying a clutch of between 5 and 15 eggs. An individual may lay several clutches during the nesting season. Incubating the eggs is not part of her role, so she must hide them well to avoid predators. Incubation is for 117 to 158 days. The hatchlings dig themselves out of the nest, being immediately independent. Red-footed tortoises typically are reproductively mature when they are usually at about 5 years of age.
The biggest threat to Red-footed tortoises being overhunted by humans. In much of their range, thousands are eaten by people, and in many South American cities, they are considered a delicacy. In underdeveloped areas, native peoples consume their eggs as a primary source of protein. They are also threatened by habitat loss and other human activity, including drainage of wetlands for housing, agriculture, logging, and road construction. Tortoises and turtles are particularly vulnerable, as humans often develop land next to rivers, lakes, and seas where these species lay their eggs. Furthermore, the demands of the pet trade impact populations so much that in the wild they may become extinct.
The total population size of the Red-footed tortoise is unknown. Presently, this species is not included in the IUCN Red List and its conservation status has not been evaluated.
