Front Cover: October 2018

Common Gallinule by Edgar Allan Slothman

October 1, 2018 4 MIN READ Front Cover

Common Gallinule

The Common Gallinule (Gallinula galeata) has had nearly 40 different common names in North America. The American Ornithologists' Union (AOU) in the late 1800s called it the Florida Gallinule and retained that name even after lumping it with the Eurasian Common Moorhen (G. chloropus) in 1923. The AOU later changed the name to Common Gallinule in 1957 and then declared it to be the Common Moorhen in 1983. The AOU changed its collective mind again in July, 2011, splitting the Western Hemisphere birds from the Common Moorhen of Europe, Africa, and Asia and making it a new species, G. galeata with an old name: Common Gallinule. The Eurasian birds became the Eurasian Moorhen. The AOU cited substantial differences in vocalizations and minor morphological differences as justification for the split.

The now Common Gallinule is a chicken-like bird—another of its common names is Marsh Hen—of freshwater ponds and marshes. The sexes are similar in plumage, dark gray below with blackish neck and head and a brownish back. The undertail coverts are white and there is a prominent white streak along the flanks. The legs are yellow and the bill is bright red with a yellow tip. Juveniles are grayish brown with pale underparts and lack the bright bill color. They can be distinguished from juveniles of American Coots and Purple Gallinules by the white flank slashes and white undertail coverts. The Common Gallinule has seven subspecies including one found in Hawaii. The North American subspecies is G. g. cachinnans.

Common Gallinules breed in freshwater marshes in southern Ontario and Nova Scotia, and through much of the eastern half of the United States, in widely scattered locations in the Southwest, and also in the West Indies. The breeders from southern Virginia to Texas along the Atlantic and Gulf coasts are year-round residents. Gallinules from inland and more northern areas migrate to the coast and they winter from North Carolina to Texas. Common Gallinules also breed from Mexico south through Central America and south to Northern Chile and Argentina. In Massachusetts, Common Gallinules are considered uncommon to rare fall migrants and rare breeders. They are rare in winter in Massachusetts.

Common Gallinules are generally monogamous, but some may also be polygynous. They may produce more than one brood per season. Pairs may remain together for more than a single breeding season. Courtship displays consist of a variety of maneuvers, including touching bills, head-feather nibbling, bowing, chasing, and the male may swim toward the female while bill-dipping. Gallinules give a wide variety of loud, harsh sounds and squawks as well as softer clucks and a repetitive ka-ka-ka-kree cackle series. The cackles are thought to be used in territorial advertisement by males, and the clucks are considered contact calls. Gallinules aggressively defend their territories by charging at interlopers with tail raised, wings arched, neck and head forward and down. They may run on the water surface at an opponent with wings flapping and neck stretched forward. Sometimes fights occur where one bird grasps an opponent with one foot and kicks it with the other foot while stabbing it with its bill.

In the north, Common Gallinules prefer cattail marshes that border freshwater ponds and shallow freshwater marshes with emergent vegetation. In southern areas, they will also utilize rice fields. They place their nests in aquatic emergent vegetation, and also on mats of floating vegetation and have even been known to use nest boxes. Often the nest is at the edge of vegetation near open water. Both parents construct the nest with a base of twigs and plant stems and lined with a cup composed of leaves. They continue to add plant material to the nest throughout the incubation period. They often build a separate brood nest that the whole family moves to after hatching. Both parents develop brood patches and both share incubation duties.

The usual clutch of 6–9 drab gray eggs covered with darker patches or spots is incubated for about three weeks until hatching. The chicks are covered with down and their eyes are open when they hatch. Within a day they can leave the nest, often to follow their parents to a brood nest. The parents bring both plant and animal food to the offspring for the first week after hatching, after which they feed on their own, although they may continue to receive some food from the parents for up to six weeks. Dispersal occurs after about 10 weeks.

Two types of cooperative breeding may occur. Juveniles may remain on territory and help feed the youngsters of a succeeding brood. Or the parent female may share a nest with a grown daughter or daughters and they may share the parental female's mate. Conspecific brood parasitism is relatively common, with females laying eggs in a nest other than their own.

Common Gallinules forage on both plants and animals, which they take from the water or from floating or emergent vegetation. They forage while swimming or walking on floating plants, or by tipping from the surface. Most of the diet consists of grass and sedge seeds, with snails dominating their animal food. They also take crustaceans, beetles, wasps, flies, and spiders—about anything small enough to swallow.

Common Gallinules expanded their range northward during the twentieth century and most populations are relatively stable. Human impact has been inconsistent: hunting and the drainage of wetlands have a negative impact, and the formation of ponds, lakes, and agricultural wetlands has generally been beneficial. Because of the wide distribution of this delightful rail and its ability to utilize some human-modified environments, its chances for survival remain strong, although in Massachusetts it is listed as a Species of Special Concern.

William E. Davis, Jr.