Chicken-Like Birds: Galliformes

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CHICKEN-LIKE BIRDS: Galliformes

PHYSICAL CHARACTERISTICS

Galliformes are medium to large in size, with a stocky body, small head, and short wings. Quails are the smallest species, weighing less than 1 ounce (20 grams) and measuring just 5 to 6 inches (12 to 15 centimeters). The wild turkey weighs 17 to 22 pounds (8 to 10 kilograms), and the domesticated turkey bred for eating can weigh up to 44 pounds (20 kilograms). The green peafowl measures up to 98 inches (250 centimeters) in length.

Galliformes have short bills that usually curve downward to assist in pecking plant material from the ground. Their feet are big and strong—so strong that they can move heavy branches or stone. Some galliform tails are one-third the size of their total body length. Both sexes are often brown or black, but the males of a few species are incredibly colorful.

GEOGRAPHIC RANGE

Galliformes are found on every continent except Antarctica.

HABITAT

Gallinaceous birds enjoy a wide variety of habitats: forests, mountains, farmland, semideserts, and savannas (plant communities characterized by shrubs and low trees as well as grasses and herbs).

DIET

The chicken-like birds eat nuts, seeds, and parts of plants. Their large feet help them move branches and stones to discover food other animals could not access. Chicks eat insects and larvae (LAR-vee; immature stage for some insects) during their first few weeks of life.

Galliformes regularly swallow small stones to help the digestive process. The rocks help break down nuts and seed coverings as well as the tough fibers that make up green vegetation. These birds don't drink much water, but a few species visit salt licks, where they eat clay soil that gives them required minerals.

BEHAVIOR AND REPRODUCTION

Social behavior varies among species. Many species are solitary (lone) or spend the year in pairs. Other species spend the nonbreeding season feeding together in larger groups.

Males are territorial. Because their vivid colorations make them easy to spot, some species move only when threatened, preferring to spend the majority of their time sitting still. Most species do not migrate. In fact, they rarely leave the area in which they were born. A few do migrate (travel seasonally from region to region), however.

Galliformes are terrestrial (land-based) and are not built for long-distance flight. They are better equipped to make strong, short bursts of flight. When threatened, they are more likely to run away than fly. When they do take flight, most species cannot fly high above the ground.

Gallinaceous birds bathe by squatting in shallow pits and beating their wings. This dusts their feathers and removes parasites.

Breeding habits vary throughout the order. Those species in which there is little physical difference between the male and female tend to be monogamous (having just one mate), whereas those in which the males are more colorful are polygynous (one male, many females). Males have many physical traits used to attract females, including bright colors, shaped tail feathers, and other distinct markings. Some have combs (fleshy red crests on top of the head) and eyebrows. One family—the curassows— has a colorful knob on the beak that gets larger as the bird ages.

Vocalizations play an important role in courtship displays and territorial rituals. They are also used to communicate with a mate. In some species, the calls can be heard for up to 4 miles (6.4 kilometers).

The family known as megapodes do not need to sit on their eggs to incubate (keep warm for hatching to occur) them. The male builds a large mound of sand or vegetation and digs into it. The female lays her eggs in the burrow, and it's up to the male to regulate the temperature of the nest, sometimes for up to eleven months until the egg hatches. In monogamous (muh-NAH-guh-mus) pairs, where each bird mates with just one other bird, both parents help care for the young.

For those species that do incubate their eggs with their own body heat, incubation time varies from seventeen days to four weeks. Clutch sizes vary from seven to twenty eggs.

Young are born with their eyes open, able to feed somewhat independently within a few hours of hatching. Hatchlings are born with colors aimed at helping them stay hidden, but those first downy feathers are replaced with brighter colors as the bird matures. Offspring leave their parents at around one year of age.

Predators include red foxes, striped skunks, chipmunks, squirrels, raccoons, snakes, and crows.

THE PLIGHT OF PHEASANTS IN MINNESOTA

According to a Star Tribune article written by Doug Smith in 2004, more than 220,000 Minnesota hunters shot one million pheasants each fall as recently as the 1960s. But throughout the four decades since, 100,000 Minnesota hunters bagged about one-third as many pheasants each year as in the 1960s. Why the drop in statistics? Intensive farming and wetland drainage have wiped out huge portions of pheasant habitat—mainly grasslands and wetlands. The birds simply aren't around to shoot.

Pheasants Forever, the only national conservation group based in the state, organized in 1982 with the hope of restoring and maintaining the pheasant population in Minnesota. Since it began, the organization claims to have spent about 14 million dollars to buy 150,000 acres (60,700 hectares) of habitat. Even so, the impact has been minimal.

Wildlife officials say federal farm programs and weather have much greater influence on pheasant populations than do habitat improvement and acquisition projects.

GALLIFORMES AND PEOPLE

As people turned from a hunter-gatherer society into a farming society, they began to domesticate several galliform species. Turkeys, chickens, and guineafowl continue to be an important part of the human diet throughout the globe. The eggs of Galliformes are highly prized, as their high yolk content is a rich protein source.

Because Galliformes are sedentary, not very active, they are easy to shoot, which makes them the most popular hunting birds throughout the world. Every year, tens of millions of Galliformes are raised and released specifically for shooting purposes. In fact, many species have been introduced into other countries for purpose of sport or decoration. These introductions have proved to be a serious threat to the native bird populations, as is habitat destruction and degradation.

CONSERVATION STATUS

Of all the galliform species, 104 are considered Threatened, at risk of extinction, or Near Threatened, could become threatened. Those under the greatest threat are pheasants and partridges. One, possibly two, species has become extinct since 1600. Hunting for adults and eggs is a serious threat to these game birds. Conservation efforts are being made throughout the world to stabilize populations, but habitat destruction is the primary threat. Those species that depend on forests are in the most critical danger, as logging for timber and clear-cutting for agriculture is on the rise.