CURASSOWS, GUANS, AND CHACHALACAS: Cracidae

PHYSICAL CHARACTERISTICS

Length in the cracids (members of the family Cracidae) varies from 16.5 to 36.2 inches (42 to 92 centimeters) and weight is 0.8 to 9.5 pounds (0.4 to 4.3 kilograms). The slim birds are long-legged with short, rounded wings and long tails. Though short, the beak is strong and lightly curved. The feet are similar to those of moundbuilders, with well-developed toes. Plumage (feathers) is black or olive brown to reddish brown, and white marks are scattered throughout. Male curassows of many species have a fleshy knob on the root of the beak or brightly colored areas of naked skin on the head.

GEOGRAPHIC RANGE

These birds are found in south Texas through tropical South America as far as central Argentina. United States is home to only one species, whereas Colombia and Brazil harbor twenty-four and twenty-two species, respectively.

HABITAT

Cracids live in tropical forest regions, plantations, and forested areas where there is a second, lighter growth of vegetation. Although most species prefer the warmth of lowlands, some do live in mountain forests of altitudes above 9,800 feet (3,000 meters).

DIET

Though mainly plant eaters, cracids also feed on insects and other small animals. They enjoy berries and small fruits whole, but will bite into bigger fruit such as guavas and mangoes. They also eat seeds, soft leaves, and buds. Unlike other Galliformes, cracids won't scratch the forest floor for their food.

BEHAVIOR AND REPRODUCTION

We don't know much about cracid life because they are such shy birds. They seem to live socially in small groups or flocks, and their nests are found in groups. They are vocal birds whose calls are loud and cacophonous (having an unpleasant sound). Some of the mountain forest-dwelling species migrate to lower altitudes during the colder months.

WHAT'S SO GREAT ABOUT RAINFORESTS?

Aside from many species of cracids, thousands of other animals live in the tropical rainforests. In fact, half of all the known animals in the world today live in the rainforest. And we're always hearing about the importance of rainforest conservation. What makes the rainforest so special?

Rainforests are home to so many diverse species because these forests are the oldest living ecosystems on the planet. Having escaped the effects of the Ice Age, some rainforests have been around for one hundred million years! When the Ice Age wiped out other living systems, the rainforest continued to thrive, so every living organism within also kept reproducing and evolving. Today, some rainforest species number in the millions.

Though you won't find jungle cats or large animals in the rainforest, it is host to a mind-boggling fifty million species of invertebrates. On a single tree alone in Peru, one scientist found more than fifty different species of ants. Despite these impressive statistics, experts estimate that 137 species of life forms become extinct every day in the rainforests, mostly due to logging and cattle ranching.

Like any ecosystem, the rainforest inhabitants have developed so that they depend upon one another for survival. When one species is removed from the system, the effect is ripple-like, and virtually all other species must adapt. In addition to animal life, the rainforest is home to numerous plant species that we have only just begun to recognize as having medicinal use.

Cracids build their nests in trees or bushes. The nest is a flat platform, usually longer than it is wide and built from twigs, plant stems, leaves, grass, and other similar items. Some of the species are polygamous (puh-LIH-guh-mus; having several mates in one season), but no one is certain about the others. Curassow hens lay two eggs; chachalacas, three; and guans, three to four. Experts believe that only the female incubates (keeps warm before hatching) the eggs. Incubation periods vary from twenty-one to thirty-six days, depending on species.

Newborns are able to leave the nest very soon after birth. They are able to fly, hop, and walk along twigs when just a few days old. Cracids spend a great deal of time in the trees, hopping from branch to branch and walking on twigs. Cracids fall prey to jaguars and other big cats.

CURASSOWS, GUANS, CHACHALACAS AND PEOPLE

Hunters in Latin America value cracids as a rich protein source. However, because the reproduction rate of cracids is so slow, the population cannot withstand intensive hunting pressure. Cracids are greatly affected by habitat destruction. Native tribes use tail and wing feathers for ornamentation.

CONSERVATION STATUS

Cracids are more threatened than any other bird family in the Americas. Twenty-three of the fifty species are threatened with extinction, or close to being threatened with extinction, including 64 percent of curassows (nine species) and 16 percent of the chachalacas (two species). About 50 percent of guans are threatened (twelve species). Primary threats are overhunting and habitat loss.

PLAIN CHACHALACA (Ortalis vetula): SPECIES ACCOUNTS

Physical characteristics: The plain chachalaca weighs 15.5 to 28 ounces (440 to 794 grams) and measures 19 to 22.8 inches (48 to 58 centimeters) long. Coloration is olive-brown.

Geographic range: This species is found in Texas, Mexico, and Costa Rica.

Habitat: Plain chachalacas live in lowland forests as well as forests at the base of mountains in Central America. They also dwell in scrub and tall brush vegetation.

Diet: The bulk of their diet is made up of fleshy fruit. They also eat green leaves, shoots, and buds as well as twigs and some insects. Though chachalacas live mostly in trees, they descend to the ground for feeding.

Behavior and reproduction: This social bird has a distinct "cha cha lack, cha cha lack" call which nearby chachalacas sing in chorus. Most humans find it an unpleasant sound.

Nests are built 3.3 to 33 feet (1 to 10 meters) off the ground in trees. Females lay two to four eggs and incubate them for about twenty-five days.

Plain chachalacas and people: Humans may eat plain chachalacas.

Conservation status: These birds are not threatened. ∎

BLACK GUAN (Chamaepetes unicolor): SPECIES ACCOUNTS

Physical characteristics: Black guans weigh 2.4 to 2.6 pounds (1.1 to 1.2 kilograms) and measure 24 to 27 inches (62 to 67 centimeters) long. The male is entirely black except for a bare blue patch on his face.

Geographic range: Found in western Panama and in Costa Rica.

Habitat: Black guans are found in mountain forests above 3,300 feet (1,000 meters) in southern Central America.

Diet: They eat mostly fruit, but also seeds and some plants. Black guans feed alone, in pairs, or in small groups.

Behavior and reproduction: Outside the breeding season, black guans live alone. They pair off during the breeding season. Females lay two to three eggs and are responsible for incubation (sitting on the eggs).

Black guans and people: There is no known in-teraction between black guans and humans.

Conservation status: Listed as Near Threatened, not currently threatened, but could become so, by the IUCN due to habitat destruction. ∎

WATTLED CURASSOW (Crax globulosa): SPECIES ACCOUNTS

Physical characteristics: This curassow weighs about 5.5 pounds (2.5 kilograms) and measures 32.2 to 35 inches (82 to 89 centime-ters) long. The male is black with a white belly and a red globe-like ornamentation above and below the bill. The female has reddish brown belly feathers and a red fleshy area between the beak and face.

Geographic range: The wattled curassow is found from Colombia and western Brazil to Bolivia.

Habitat: This bird prefers the tropical rainfor-est in the Amazon basin. It rarely leaves the trees except to breed..

Diet: Wattled currasows feed on vegetation and small invertebrates (animals without backbones).

Behavior and reproduction: The wattled curas-sow whistles softly for four to six seconds at a time. Nothing is known about this bird's repro-ductive habits in the wild. In captivity, the female lays two eggs.

Wattled curassows and people: These birds are hunted for food, often to the detriment of the bird population.

Conservation status: Listed as Vulnerable, fac-ing a high risk of extinction, by the IUCN. Hu-mans rarely see wattled curassows not only because of the patchy distribution of the species, but because it lives primarily in higher altitudes where there are fewer people. The main threat to the wattled curassow is overhunting. ∎

FOR MORE INFORMATION

Books:

Brooks, Daniel M., and Stuart D. Strahl. Cracids: Status Survey and Conservation Action Plan for Cracids 2000–2004. Gland, Switzerland: IUCN, 2001.

Kricher, John. A Neotropical Companion, 2nd ed. Princeton, NJ: Princeton University Press, 1999.

Web sites:

"About Rainforests: Tropical Rainforest Animals." Kid's Corner, Rainforest Action Network. http://kids.ran.org/kidscorner/rainforests/s06_animals.html (accessed on June 2, 2004).

"Plain Chachalaca." Animals Online. http://www.animals-online.be/birds/hokkos/plain_chachalaca.html (accessed on June 2, 2004).

"Plain Chachalaca." ENature. http://www.enature.com/fieldguide/showSpeciesRECNUM.asp?recnum=bd0640 (accessed on June 2, 2004).