Chapters 1 - U.S. Fish and Wildlife Service

Refuge Resources
throughout southern California is presented to the public by the Refuge Manager and volunteers
during a variety of Refuge activities, including monthly Refuge tours and special guided birding
tours. The Friends of Seal Beach NWR also attend off-refuge events where they provide
information about the endangered species protected on the Refuge.
4.3.5.2 Light-footed Clapper Rail (Rallus longirostris levipes)
The light-footed clapper rail is a hen-sized marsh bird that is long-legged, long-toed, and
approximately 14 inches (36 centimeters) long. It has a slightly down-curved beak and a short,
upturned tail. Males and females are identical in plumage. Their cinnamon breast contrasts with
the streaked plumage of the grayish brown back and gray and white barred flanks.
The light-footed clapper rail uses southern California coastal salt marshes, lagoons, and their
maritime environs. The birds typically nest in the lower littoral zone of coastal salt marshes where
dense stands of cordgrass are present. They have also been known to reside and nest in
freshwater marshes, although this is not common. They require shallow water and mudflats for
foraging, with adjacent higher vegetation for cover during high water (Massey et al. 1984).
Very limited evidence exists for inter-marsh movements by light-footed clapper rails. This
subspecies is resident in its home marsh except under unusual circumstances. Movement within
the marsh is also confined and generally of no greater spread than 1,300 feet (400 meters) (Zembal
1989). Minimum home range sizes for nine clapper rails that were radio-harnessed for telemetry at
Upper Newport Bay varied from approximately 0.8 to 4.1 acres. The larger areas and daily
movements were by first year birds attempting to claim their first breeding territories.
Light-footed clapper rails forage in all parts of the salt marsh, concentrating their efforts in the
lower marsh when the tide is out, and moving into the higher marsh as the tide advances.
Foraging activity is greatest in the early morning, while vocalizing shows a strong peak just before
dark. Activities are also tide-dependent. The rails are omnivorous and opportunistic foragers.
They rely mostly on salt marsh invertebrates, such as beetles (Coleoptera), garden snails (Helix
spp.), California hornsnails, salt marsh snails (Melampus olivaceus), fiddler and hermit crabs
(including Pachygrapsus crassipes, Hemigrapsus oregonensis, and probably Uca crenulata),
crayfish, isopods, and decapods. This species may also forage on frog tadpoles (Hyla spp.),
California killifish, and even California meadow mice (Microtus californicus). The rails ingest
some vegetable matter, including cordgrass stems and pickleweed tips, but this is uncommon.
The pair bond in light-footed clapper rails endures throughout the season, and often from year to
year. Nesting usually begins in March and late nests have usually hatched by August. Females
lay approximately four to eight eggs, which hatch in 18-27 days. Both parents care for the young.
While one adult is foraging, the other adult broods the chicks. By the age of two days, chicks will
accompany adults on foraging trips; however, adults have been observed feeding fully grown chicks
of at least six weeks of age within 82 feet (25 meters) of their incubation nest. This incubation nest
is a second nest constructed by the rails and is used for brooding the young.
Typically, light-footed clapper rail nests are placed to avoid flooding by tides, yet in dense enough
cover to be hidden from predators and support the relatively large nest. Cordgrass provides the
preferred nesting habitat for light-footed clapper rails. Massey et al. (1984) describes the classical
clapper rail nest as follows:
A nest, built in the low littoral zone in a stand of tall dense cordgrass, constructed primarily of
dead cordgrass stems. The platform of the nest is built up from the ground or supported in the
cordgrass, the rim level as high as 45 centimeters off the ground. A canopy of live cordgrass
Draft Comprehensive Conservation Plan/Environmental Assessment 4-63