Red-Legged Seriemas
South America's tropical rainforest and its spectacular plants and animals get so much attention that it's easy to forget that there are other South American habitats that boast equally interesting species. East of the Andes and south of the Amazon, for instance, are partly open, fairly dry habitats ranging from savanna-like grasslands to arid woodlands.
Long-legged maned wolves live here, as do capybara, the world's largest rodents, and giant anteaters with very long snouts. The Chaco, dry wooded lowland habitat in parts of Bolivia, Paraguay, and Argentina, is the only home of the Chacoan peccary. This large mammal, weighing between 65 and 90 pounds, was first identified by scientists in the 1970s. Two species of rheas, very large flightless birds resembling ostriches, also wander the open plains. Then there are seriemas, large predatory birds with long legs, necks, and tails.
Two closely related species of seriema stalk parts of South America. The black-legged seriema (Chunga burmeisteri) is the smaller and lesser known of the two, and occupies a smaller range. The larger red-legged seriema (Cariama cristata), the species found at the National Zoo, stands up to three feet tall and may weigh more than three pounds.
This striking bird's slender legs are the color of wild salmon, and its bill is a carroty red. Its large yellow irises are almost cat-like, and bare skin around the eyes is blue. It also sports a three- to four-inch-long crest of feathers that bristles from its forehead like an open fan. More remarkable than the seriema's physical charms, however, is its voice, so frequently heard that the seriema's song characterizes the soundscape of its habitat.Usually compared to turkey gobbling or young dogs yelping, the song is very long and very loud, audible to human listeners a few miles away. When one member of a pair sings, the other usually joins in; their young, which begin to sing at two or three weeks old, may add their voices to the cacophony. So too may other pairs or groups in the vicinity. The better to be heard, the birds often sing from atop a termite mound or from high in a tree. Seriema pairs are believed to use song to defend their territories, which are probably quite large, as is typical for predators.
Although seriemas can fly, they rarely do. They usually run to escape danger, and can reach speeds of 15 to 25 miles per hour or more. They also hunt on the ground, stalking prey that includes grasshoppers, beetles, and other insects, as well as frogs, snakes, lizards, bird chicks, and rodents.
They catch prey in their beaks, then eat small prey whole or tear larger animals apart with their feet and hooked beaks. To kill larger prey, they hold the victim in their beak and either slam or thrown it against the ground. In the Zoo, they eat mice, horsemeat, crane pellets, and mealworms.
In the wild, a seriema pair builds a nest of sticks and twigs in a tree, but the nest is sited so that the birds can walk and jump to reach it, rather than fly. At the Zoo, keepers provide sticks for the birds to add to their nest. The nest is a sturdy wire basket mounted on a metal post about five feet off the ground. It is set back in some bushes to give the birds some privacy.
The female usually lays two eggs, which hatch in 24 to 30 days. It is common, however, for only one of the two chicks to survive to fledging at about one month of age. Young reach adult weight and develop adult plumage at four to months. The Zoo's six-year-old female laid her eggs on March 28. Her mate is eight years old. This pair has been raising chicks since 1998.
Bird keeper Sara Hallager maintains the North American studbook for the species, which are found in only 23 zoos, for a total of about 50 individuals in North America. The new chicks will stay with their parents until October at which point they will be old enough to be transferred to other zoos. They will become part of breeding programs at these institutions.
While not considered endangered in the wild, little is actually known about their numbers in various parts of their range and some scientists suggest that the fact that they are so easily heard leads to overestimates of their abundance.
The genus name Cariama if from a Tupi Indian word for "crested." The Brazilian word seriama is from this, influenced by the word "Ema," which is the greater rhea.
Photos by Jessie Cohen/NZP
