Light-footed Clapper Rail

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Light-footed Clapper Rail

Rallus longirostris levipes

StatusEndangered
ListedOctober 13, 1970
FamilyRallidae (Rails, Gallinules, Coots)
DescriptionHenlike marsh bird with a long, slightly down-curved bill.
HabitatCoastal salt marshes.
FoodInsects, small fish, snails, plant matter.
ReproductionClutch of four to eight eggs.
ThreatsLoss of wetlands.
RangeCalifornia; Mexico (Baja California)

Description

The light-footed clapper rail is a compact, hen-like marsh bird, with a long, slightly down-curved bill. Measuring 14-16 in (35-41 cm) in length, this rail has a tawny breast, a gray-brown back, vertical dusky and white bars on its flanks, and a white patch under its short up-cocked tail.

Behavior

The light-footed clapper rail is an omnivorous forager, feeding on snails, crustaceans, insects, tad-poles, and small fish, as well as some plant matter. It is usually a year-round resident in its home marsh and is primarily sedentary. Clapper rails nest from mid-March to mid-August, and most eggs are laid from early April to early May. Clutch size ranges from four to eight eggs, which are incubated for about 23 days. Both parents attend the nest, which is constantly incubated during daylight hours.

After the chicks hatch, the parents construct two or more brood nests out of dried cordgrass. Both parents care for the young; while one forages, the other broods the chicks. After a few days, chicks accompany adults on foraging trips.

Habitat

Clapper rails require saltwater or brackish marshes, with adequate vegetation for nesting, foraging, and cover. Nests are built under clumps of pickleweed, often placed directly on the ground or in stands of cordgrass slightly above ground level.

Distribution

When originally described, the light-footed clapper rail ranged widely in salt marshes along the Pacific coast, from Santa Barbara County, California, to the Bay of San Quintín, Baja California, Mexico. Some ornithologists, questioning the identification of birds at the lower end of the range, place the southern boundary at Ensenada, Baja California. Within this range, most salt marshes along the coast at one time supported breeding populations of light-footed clapper rails.

As of 1990, light-footed clapper rails were found in 21 California marshes and at least two in Baja California. Nearly 90% of the U. S. population inhabits only six marshes. The greatest concentration of rails is at Upper Newport Bay in Orange County. Other locations having sizable rail populations include the Kendall-Frost Ecological Reserve and Tijuana Marsh in San Diego County, Anaheim Bay in Orange County, and Goleta Slough in Santa Barbara County. In the early 1970s the California light-footed clapper rail population was estimated at 500-700 pairs. By 1986 only 143 pairs were estimated to survive within the state.

Threats

The major factor in the decline of the light-footed clapper rail has been the destruction or degradation of its salt marsh habitat. Dredging and filling of marshes has continued all along the California coast, particularly around San Diego, Mission Bay, and the Los Angeles-Long Beach area. In southern California only about 25% of the wet-lands that existed in 1900 remain. In remnant wet-lands, various natural phenomena threaten the surviving rail population. Violent storms and excessive runoff can severely damage the marsh community. Nesting vegetation may be torn away or matted down so it is unusable, and nests are often lost to above-normal tides. Because most nests are built on or close to the ground, predation has contributed to the decline.

Conservation and Recovery

Since 1979, several marshes have been restored, and several other areas of marshland have been protected, including Anaheim Bay and Upper Newport Bay in Orange County; Goleta Slough in Santa Barbara County; and South Bay Marine Reserve, Tijuana Marsh, and Kendall-Frost Ecological Reserve in San Diego County. One recovery technique that has worked well is the provision of artificial nesting platforms. Designed to float up and down with the tides, platforms in the Anaheim Bay National Wildlife Refuge were used extensively during the 1986 and 1987 breeding seasons. Similar platforms were later constructed at Point Magu, Carpenteria Marsh, and the Kendall-Frost Ecological Reserve.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

References

Massey, B. W., et al. 1984. "Nesting Habitat of the Light-Footed Clapper Rail in Southern California." Journal of Field Ornithology 55: 67-80.

U. S. Fish and Wildlife Service. 1985. "Recovery Plan for the Light-Footed Clapper Rail." U. S. Fish and Wildlife Service, Portland, Oregon.