King Rail

© Judd Patterson

Scientific name: Laterallus jamaicensis

State Status: Threatened
Federal Status: Not Listed

Description

The king rail is the largest and rarest of the secretive, marsh-dwelling rail species found in New York. It measures 15 to 19 inches in length, has a wingspan of 21 to 25 inches, and weighs approximately 12 ounces. A tall, narrow body and long toes allow it to move silently and unnoticed among the floor of the cattail marsh. The black and yellow bill is long with a slight downward curve. A rusty-colored breast gives way to alternating light orange and black-striped flanks, a light orange, buff, and black streaked backside, and a short, uplifted tail.

It is similar in appearance to the clapper rail. Differentiating between these similar rails becomes more problematic when their ranges overlap in areas where freshwater meets brackish water; these species are known to hybridize in such locales. The king rail is most vocal during the breeding season. The male advertising call is a harsh and loud kik-kik-kik and the contact call given by both sexes throughout the year is described as jupe-jupe-jupe, similar, but slower than the clapper rails call.

King rail range map from Birds of the World,
maintained by the Cornell Lab of Ornithology.

Life History

King rails initiate nesting within their northern range in late April or early May. They lay six to 14 eggs in a platform nest consisting of grasses, sedges, and rushes which is placed just above the water in a clump of tall grass. A canopy top and ramp leading up the side complete the construction of the nest. Both sexes share the responsibility of incubation for approximately 21 days, and feeding chicks for up to six weeks after hatching. King rails feed predominantly on crayfish and aquatic insects. They forage under the cover of marsh vegetation, or in more open areas not far from protective cover.

Distribution and Habitat

King rails utilize a variety of wetlands including brackish coastal marshes, tidal and non-tidal freshwater cattail marshes, prairie swamps, shrub swamps, and rice fields. Their range extends from southern Ontario to the Gulf Coast of Mexico, east to the low-lying areas of the Mid-Atlantic States, and west to the Mississippi. Isolated populations also occur in Cuba and central Mexico. Northern breeding populations are migratory while southern populations are generally year-round residents. In New York, scattered breeding records have occurred in the southern Hudson River Valley and within large wetlands associated with the Great Lakes.

Status

Little is known about the biology and population status of North America's rail species because of their secretive behavior and difficult to access habitat. Standard roadside surveys, such as the Breeding Bird Survey, do not yield reliable estimates of king rail population trends. However, surveys at historic sites that once supported abundant king rail populations have led many biologists to believe that king rails have experienced a significant decline over the past 40 years.

Distribution of king rail in New York from
1st and 2nd NYS Breeding Bird Atlas records.

Possible reasons for this decline are wetland loss and habitat degradation from contaminant and agricultural run-off, increased occurrence of several invasive plant and animal species, dredging and stream channelization, and fragmentation of large wetlands. The king rail is listed as federally endangered in Canada. In the U.S. it is considered a "Bird of Special Concern" and a "Gamebird Below Desired Condition" (Cooper 2007).

Hunting for king rails is allowed in many states, particularly in the south where populations may be more secure. However, it is listed as threatened or endangered by 12 states. Several other states that have not given it a special status listing have closed the hunting season.

Management and Research Needs

Research and monitoring are important components of king rail conservation. A National Marsh Bird Monitoring Program is underway in several states, including New York. The goal of the program is to assess the current status and distribution of marsh birds by conducting surveys designed to increase detection of these secretive birds and identify key habitat components for effective management. More research on breeding biology and survival rates is also necessary to fully understand the population dynamics and the effect of harvest on the king rail.