Tinamous: Tinamidae

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TINAMOUS: Tinamidae

HIGHLAND TINAMOU (Nothocercus bonapartei): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Tinamous (TIN-ah-mooz) range in size from 8 to 21 inches (20 to 53 centimeters) and weight from 1.4 ounces to 5 pounds (43 grams to 2.3 kilograms). They have a compact body, thin neck, a small head with a beak that curves slightly downward, short wings and tail, and fly infrequently. They have thick, medium-length legs with three toes pointing forward and one pointing backward. They also have a preen gland that secretes an oil they use for grooming.

Tinamous are various shades or gray or brown, with streaky, barred, or mottled patterns. Their coloring is cryptic, meaning it helps them blend in with their surroundings. This makes them harder to be detected by predators, including humans, foxes, armadillos, and skunks. Females are generally larger than males and have somewhat brighter feather coloring.

GEOGRAPHIC RANGE

Tinamous are found in southern Mexico and throughout Central and South America, including Argentina, Bolivia, Brazil, Belize, Chile, Colombia, Costa Rica, Ecuador, El Salvador, Guyana, Guatemala, French Guiana, Honduras, Nicaragua, Panama, Paraguay, Peru, Surinam, Uruguay, and Venezuela.

HABITAT

Tinamous occupy a wide variety of habitats. Some species live in tropical rainforests, others in bush woodlands and the edges of forests. Several live in arid or semiarid grass-covered treeless plains or grasslands. Several species live in the alpine tundra of the Andes Mountains.

DIET

Tinamous eat a mostly herbivorous (consists of plants) diet consisting of seeds, roots, fruits, berries, tender leaves, and flowers. They also on occasion will eat insects and their larvae (LAR-vee), spiders, termites, ticks, worms, snails, and slugs. Several species will eat small vertebrate animals, those with a backbone, such as lizards, frogs, and mice.

BEHAVIOR AND REPRODUCTION

Tinamous are one of the oldest families of birds. They are diurnal, meaning they are most active during the day. They are very shy and are rarely seen by humans. When approached, they hide in ground cover or heavy brush. Although they can fly, they rarely do, preferring to spend most of their time on the ground. They walk and run quickly. Most species roost, or sleep, on the ground, although a few sleep in trees.

When a tinamou feels threatened, it will stand or crouch motionlessly, or walk into heavy brush. When frightened, they will beat their wings and make a loud crowing or barking noise. As a last resort, they will fly low and for a short distance.

Most tinamous are polygamous (puh-LIH-guh-mus), meaning they take more than one mate during a breeding season. The exception is the ornate tinamou, of which a single male and female pair off. For some species, the breeding season is year-round. For others, it is only during a four-month time period each year. At the start of the breeding season, a male will establish its territory and build a nest by digging a shallow hole in the ground, usually among trees or grasses.

The male will call out to attract females. Usually, two or more females will respond and lay eggs in the nest. The male incubates (keeps warm until hatching) the eggs for seventeen to twenty-one days. A few days after they hatch, the chicks leave the nest and the male signals for new females to lay eggs. Tinamou eggs are among the most beautiful of all birds, coming in a variety of deep, shiny, solid colors, including red, brown, black, gray, olive, purple, sky blue, and bright green.

Nesting habits are not uniform among tinamou. The male variegated tinamou incubates a single egg while the male ornate tinamou incubates four to nine eggs from a single female. The ornate tinamou female aggressively defends the breeding territory, a task done by males in other tinamou species.

The two most common species of tinamou are the variegated tinamou and the crested tinamou (also commonly known as the elegant crested or Martineta tinamou). They live throughout the open grasslands, or pampas, of South America. The Chilean tinamou lives in the tundra-like areas of the southern Andes Mountains in southern South America. It was introduced to Easter Island in the South Pacific in the late nineteenth century, where it still thrives today.

Tinamous were imported into Europe and Canada in the early 1900s and raised as game birds, but domestication was not successful.

TINAMOUS AND PEOPLE

Tinamous are hunted by humans for their meat, which is said to be tender and flavorful. Because of this excessive hunting, coupled with destruction of its habitat, tinamou populations are declining.

HATES TO FLY

The closest living relatives to tinamous are ratites, a group of flightless birds that includes the ostrich. Tinamous have small wings and can make only short flights. Their tail, important in steering while flying, is extremely short. This causes them to often lose control on takeoff and fly into obstacles. They only fly when they feel they are in immediate danger.

CONSERVATION STATUS

Two species of tinamou are listed by the World Conservation Union (IUCN) as Critically Endangered, facing an extremely high risk of extinction: the Magdalena tinamou and Kalinowski's tinamou. Four species are listed as Vulnerable, facing a high risk of extinction: the black tinamou, dwarf tinamou, Taczanowski's tinamou, and Choco tinamou. Four species are listed as Near Threatened, in danger of becoming threatened: the solitary tinamou, pale-browed tinamou, yellow-legged tinamou, and Colombian tinamou.

HIGHLAND TINAMOU (Nothocercus bonapartei): SPECIES ACCOUNT

Physical characteristics: The highland tinamou is 15 inches (38.5 centimeters) long and weighs 2 pounds (0.9 kilograms). Its coloring is mottled (spotted) or barred with black and cinnamon on its back and wings. Its throat is usually rust-colored.

Geographic range: Highland tinamous live in Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela.

Habitat: This tinamou lives in tropical and subtropical rainforests, usually above 5,000 feet (1,500 meters). The highland tinamou prefers wet areas, especially ones with bamboo thickets.

Diet: The highland tinamou eats mainly fruits and small animals and reptiles, such as lizards, frogs, and mice.

Behavior and reproduction: The male highland tinamou makes a rough and hollow-sounding crowing or barking call that can be heard for several miles (several kilometers). He makes the sound repeatedly while in his home territory. The male defends his territory and attracts a harem of three females with his calls. He builds a nest in dense vegetation where the females each lay three eggs. The male sits on the nine eggs until they hatch. He usually leaves the nest no more than once a day to look for food.

Highland tinamous and people: The highland tinamou is hunted by humans for its meat. As a result, populations are declining in Peru and Costa Rica.

Conservation status: The highland tinamou is not considered threatened by the IUCN. ∎

FOR MORE INFORMATION

Books:

Clements, James F. Birds of the World: A Checklist. Vista, CA: Ibis Publishing Company, 2000.

Davies, S. J. J. F., et al. Bird Families of the World. Vol. 8, Ratites and Tinamous: Tinamidae, Rheidae, Dromaiidae, Casuariidae, Apterygidae, Struthionidae Oxford, U.K.: Oxford University Press, 2002.

De la Pena, Martin R., and Maurice Rumboll. Birds of Southern South America and Antarctica. Princeton, NJ: Princeton University Press, 1998.

Feduccia, A. The Origin and Evolution of Birds, 2nd ed. New Haven, CT: Yale University Press, 1999.

Perrins, Christopher M., and Alex L. A. Middleton, eds. The Encyclopedia of Birds. New York: Checkmark Books, 1985.

Sibley, David Allen. The Sibley Guide to Birds. New York: Knopf, 2000.