Family: Cariamidae
Genus/Species: Cariama cristata
Description
Male and female Red-legged Seriemas look alike, although males are slightly larger than females. Both weigh about 1.5 kg, and stand approximately 90 cm. Their most striking feature is the crest, which is unique among South American birds. The crest is comprised of permanently raised slightly stiff feathers at the base of the bill which can reach 10 cm in length. Seriemas are one of the few birds with eyelashes. Seriemas have loose plumage, especially on the neck and underparts. They are mainly gray in coloration, with shades of brown, except the abdomen which is white. The wing and tail feathers are banded black and white. The skin surrounding the eye is blue and the iris of the eye is yellow. The bill and legs are both red.
Being mostly ground dwelling birds, seriemas have three short, very sharp front toes, and a raised, slightly smaller hind toe. They are quick runners, generally preferring to run from danger than fly. Perhaps one of the most distinguishing characteristics of seriemas, is their call. Often compared to that of a yelping puppy, it is a loud cry which can be heard from several kilometers away. The call is usually performed in the early morning hours, but may be heard at any time of day. It is used to defend territory between pairs. The call is usually initiated by one member of the pair, followed by the other member responding, with a sort of duet resulting.
Distribution and Habitat
The Red-legged Seriema is found in South America in central and eastern Brazil through eastern Bolivia and Paraguay, to Uruguay and central Argentina. It can be found in lightly wooded areas, and also open savanna type areas. The main concentration of Red-legged Seriemas is in the grassy savanna-like habitat of central Brazil. Further south, seriemas are found in more wooded areas, as well as grasslands. They can be found at elevations of 2000 m. Seriemas have recently colonized man-made grassy areas, and other semi-open areas of Brazil which were formerly covered by tropical forests.
Diet
Although seriemas are omnivores, they are highly carnivorous. Their diet includes insects, especially grasshoppers and beetles. They also eat a large number of small rodents, lizards, frogs, and birds. Their reputation of consuming large numbers of snakes is exaggerated. Leaf material is consumed, as in seeds, fruits, and crops cultivated by man such as corn, beans, and grains. They swallow small prey items whole, head first. Larger animals are held between their sharp claws and torn apart. Killing their prey may involve beating the animal on the ground, or throwing it against a hard surface such as a rock.
Reproduction
Seriemas are considered to be a monogamous species. In the wild, the breeding season corresponds to the rainy months of May to September. Courtship display is done by the male and involves showing off the flight feathers by stretching them to one side. This is also accompanied by strutting in front of the female, with head pointed down and crest raised. Both sexes assist in nest building which takes about one month. The nest, which is usually in a tree 1-5 meters above the ground, is made of twigs and branches and lined with mud and leaves.
Generally, two white, slightly speckled eggs are laid. Incubation is carried out by both sexes for 25-30 days. The chicks are covered in long, light brown feathers. They are fed by both parents and are able to leave the nest at about 12-15 days where they follow their parents around on the ground. Even at this age, the chicks are able to produce a call similar to the adult vocalization, and may assist the parents with defense of the territory. Chicks fledge at one month. Sexual maturity has been reported at eight months in captivity.
Conservation
The Red-legged Seriema is not considered a threatened species. Although their traditional habitat is changing due to human interference, seriemas seem to have adapted to these changes. However, exact counts of the species have not been conducted, so their true status is not known. Further complicating the matter is their far reaching call, which may yield a false count of the actual number.
In central Brazil, the Red-legged Seriema is more often heard than seen, while in the southern part of the country it is considered uncommon. In Argentina, numbers range from abundant to scarce. It is considered a vanishing species in Uruguay. Fortunately, this species breeds easily in captivity, so zoos can continue to exhibit this species without relying on wild-caught individuals. The National Zoo assists in the captive maintenance of seriemas by keeping the North American studbook for the species.
References
del Hoyo, J., Elliot, A. and Sargatal, J. eds. Handbook of the Birds of the World. Vol. 3. Hoatzin to Auks. Lynx Edicions, Barcelona. 1996.
Photo by Jessie Cohen, NZP
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