Limpkin: Aramidae

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LIMPKIN: Aramidae

PHYSICAL CHARACTERISTICS

Limpkins are medium-sized gruiform (member of the order Gruiformes) species that have long legs with spread toes, a long, downward-curving bills, and rounded wings and tails. Limpkin bills curve slightly to the right at the tip, a feature that helps them extract its primary prey item, the apple snail, from its shell. There is also an unusual, small gap in the bill which appears to help limpkins carry and manipulate apple snails. Finally, the tip of the upper bill is sharpened and used to cut snails from their shells. Limpkins are primarily dark brown in color although there are white spots on the neck, breast, and the outside surface of the wings. Limpkins are about 26 inches (66 centimeters) in length and can weigh up to 2.4 pounds (1.1 kilograms). They have a wingspan of approximately 40 inches (102 centimeters). Male and female limpkins are generally similar in size and coloration.

GEOGRAPHIC RANGE

Limpkins are found only in the Western Hemisphere, from Florida through most of Mexico, the West Indies, and Central America. They are also in South America east of the Andes mountain range and as far south as central Argentina.

HABITAT

Limpkins generally occur in wetland habitats, including shallow-water areas near ponds, lakes, and slow-moving rivers.

DIET

Limpkins are highly specialized feeders, meaning they focus on very few food items and have special adaptations which help them deal with their diet. The limpkin's primary prey is the apple snail, a large freshwater mollusk which occurs throughout the range of limpkins. Limpkins search for apple snails in the muddy bottoms of shallow bodies of water, trying to find them either visually, or by prodding the mud with their long bills. They search for food in the open, as the cranes do. Once a limpkin finds a snail, it carries it to shallow water to cut it from its shell and eat it. Although adult limpkins never swallow snails whole, young limpkins do. Young limpkins are brought small snails by their parents and swallow them entire. Although apple snails form the bulk of their diet, limpkins may also eat mussels, insects, crayfish, small reptiles or frogs, and the seeds of some plants.

BEHAVIOR AND REPRODUCTION

Most limpkins are solitary, they live alone. In some cases, limpkins may be found in pairs, usually male and female breeding partners, or in small groups. Limpkins are good swimmers and slow but strong fliers. The name limpkin comes from the slightly awkward walk of the species. However, limpkins are in fact strong runners. At night, limpkins tend to roost either in shrubs or in the tops of dead trees. Most limpkins are not migratory, spending the entire year in one location. However, some South American limpkin populations move between a wet season habitat and a dry season habitat.

The limpkin is the only species in the family Aramidae and has no close relatives. However, within the Gruiformes, similarities to both cranes and rails have long been noted. In particular, the general physical appearance and hunting behavior of limpkins resemble that of cranes, but other aspects of behavior, including a more secretive nature, resemble that of rails and their relatives.

SNAIL EATERS

The apple snail is important to the limpkin's diet. Limpkins have several physical adaptations that help it deal with this prey. Since the apple snail's shell curves to the right, limpkins adapted a bill that also curves to the right, making it possible to insert the bill into the snail shell. The tip of the upper beak is sharpened to allow limpkins to cut the snail out of the shell. Finally, limpkins have a small gap in the bill which helps them carry and handle snails.

The call of a limpkin is extremely distinctive. It is a loud, wild-sounding scream or wail that is frequently described as a "kree-ow kree-ow" sound. The call is given most often in the early morning or at night, as well as on cloudy days. This loud, distinctive cry accounts for some of the nicknames the limpkin has picked up in parts of its range. These include wailing bird, crying bird, and crazy widow. Limpkins also make a quieter clicking noise.

Limpkins build their nests near water. Most often, nests are built either on the ground, hidden in dense vegetation, or up in a tree. In some cases, nests may be 20 feet (6 meters) off the ground or even higher. Nests are built from reeds and grass and lined with softer plant material. In general, four to eight eggs are laid at a time by the female. The eggs range from white to pale brown in color, and may or may not be lightly spotted. Both male and female limpkins participate in all phases of reproductive activity, including nest-building, incubating the eggs, and feeding and caring for the young once they hatch. Limpkin young are precocial (pree-KOH-shul), meaning they are fairly developmentally advanced when they hatch, being covered with down (rather than featherless) and able to move. Limpkin chicks are able to leave the nest about one day after hatching, and follow one of the parents around until they become independent.

LIMPKINS AND PEOPLE

Limpkins were once hunted for meat, but hunting is no longer common. Now they are important in the tourist industry, attracting birdwatchers in many parts of their range. Limpkins are also important to many local cultures, and are particularly well-known for their powerful wailing cries.

CONSERVATION STATUS

Limpkins are not considered threatened at the present, although they have been designated a "species of special concern" in Florida, the only place in the United States where they occur. However, at the beginning of the twentieth century, limpkins were almost hunted to extinction in the U.S. for their meat. Protection since then has allowed many populations to recover. At present, many limpkin populations are again declining due to damage and destruction of the wetland habitats they require.