Trumpeters: Psophiidae

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TRUMPETERS: Psophiidae

COMMON TRUMPETER (Psophia crepitans): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Trumpeters range from 17 to 21 inches (43 to 53 centimeters) in length, and are approximately 2.2 pounds (1 kilogram) in weight. They have black feathers and, depending on the species, a paler patch of gray, green, or white on the back from the folded inner wing feathers. Trumpeter chicks, which are colored to blend into their environments, have brown and black stripes. Trumpeters have hunched backs, long necks which are usually held close to the body, small heads, long legs, and short tails. The bill is short and sharp. Males and females are similar in appearance, although males tend to be larger in size.

GEOGRAPHIC RANGE

Trumpeters are found in northern South America, including portions of Venezuela, Colombia, Ecuador, the Guianas, Peru, Bolivia, and Brazil.

HABITAT

Trumpeters live in areas of tropical rainforests where there are many trees and little ground cover. Because they are primarily fruit eaters, their habitats generally have many fruit trees.

DIET

Trumpeters eat primarily fruit, with their favorites being soft fruits with thin skins. Trumpeters rely largely on monkeys to knock fruit onto the ground, since they are not able to fly up to high trees themselves. They also take advantage of fruits that grow on low bushes. Trumpeters also eat large numbers of insects off the forest floor, particularly beetles, ants, and termites. On occasion they will also eat larger animals, such as small snakes.

BEHAVIOR AND REPRODUCTION

Trumpeters are found in large groups which include a single dominant female and several males whom she breeds with, as well as their young. All adult trumpeters participate in feeding and caring for the young. This reproductive system, which is rare among birds, is known as cooperative polyandry (PAH-lee-andree). As with many species where many individuals live together, dominance relations, a system where some individuals have higher rank and others have lower rank, are well established among individual trumpeters. Subordinate individuals in the group, those with lower rank, often crouch and spread their wings in front of the dominant individuals. Trumpeters also preen each other, or clean each other's feathers, feed each other, and engage in mock fights. All these behaviors help to strengthen bonds between individuals in the group.

Groups of trumpeters are highly territorial, defending their territories against other trumpeters. In order to find enough food during the dry season, trumpeter groups require large territories. When a group of trumpeters finds other trumpeters in their territory, they sneak up on the intruders, then scream the loud, distinctive calls which give trumpeters their name. Fights involve kicking and pecking, and continue until the intruders leave the territory. At night, trumpeters roost in trees, sometimes in branches as high as 30 feet (9 meters) off the ground. Even at night, trumpeters make their loud territorial calls every few hours.

FOOD, SOCIABILITY, AND TERRITORIALITY

Trumpeters are social birds, found in close-knit groups of as many as a dozen individuals. These usually consist of a single dominant female, up to three dominant males, and their young. It is believed that trumpeters form large groups to defend their large territories from other groups of trumpeters. The large territories, in turn, are necessary for trumpeters to find as much food as they need.

A single dominant female in the trumpeter group mates with as many as three dominant males. All adults help to feed and care for the young. Trumpeters like to build their nests in tree cavities, holes in trees which have been dug and abandoned by other birds. The nest is built from sticks. Before the act of mating takes place, the male feeds the female. The female then walks in a circle showing her back end while the male follows. Generally, the female lays three white eggs at a time. All the adults help incubate, or sit on, the eggs until they hatch, although the majority of the incubation is performed by the female and the dominant male. Chicks depend on adults to feed them for several weeks. They are unable to fly at first, so roost, or spend the night, close to the ground rather than high in trees like adult trumpeters. Because of this, many are eaten by snakes, predatory birds, and other species. Only about half the trumpeter chicks that hatch survive to become adults.

TRUMPETERS AND PEOPLE

Trumpeters interact with humans in a variety of ways. They are kept as pets in some parts of their range. Some people use trumpeters in chicken coops to alert humans when there are snakes. Trumpeters are also hunted for food in some areas. Because trumpeters tend to stay with their group, even in the face of danger, they often make easy targets for hunters.

CONSERVATION STATUS

Trumpeters are not considered threatened. However, because their rainforest habitats are being destroyed in many parts of their range, and because trumpeters require large territories in order to find enough food, many populations are declining. In addition, some of the monkey species which trumpeters depend on to obtain fruit are in trouble because of habitat loss and hunting. This is harming trumpeter populations as well.

COMMON TRUMPETER (Psophia crepitans): SPECIES ACCOUNT

Physical characteristics: Common trumpeters are 18 to 20 inches (42 to 52 centimeters) in length and 2 to 3 pounds (1 to 1.5 kilograms) in weight. They are dark in color with a patch of light gray on the back. They have long legs and a long neck. Young common trumpeters are dark gray with reddish stripes.

Geographic range: Common trumpeters are found in northwestern Brazil as well as portions of Colombia, Ecuador, Peru, Venezuela, and the Guianas.

Habitat: Common trumpeters are found in dense areas of tropical rainforest.

Diet: Common trumpeters eat fruit, mostly that which has been knocked to the ground by monkeys. They also eat some insects, particularly beetles, ants, and termites.

Behavior and reproduction: The common trumpeter is generally found in groups of three to twelve individuals. A single dominant female mates with as many as three dominant males. Three eggs are laid at a time, usually in a hole in a tree. Eggs hatch after approximately twenty-eight days. All adults in the group help in feeding and caring for the offspring.

Common trumpeters and people: Common trumpeters are sometimes hunted for food.

Conservation status: The common trumpeter is not considered threatened. However, populations have been declining due to the loss of tropical rainforest habitat as well as hunting. ∎