Current Distribution Rangewide

Range in California extends from Ventura County-Mugu Lagoon-in the north to the the Mexican border in the south. Distribution within range is discontinuous because salt marsh habitats occur sporadically along the coastline [1].

Known Populations in San Diego County

Pairs detected in Buena Vista Lagoon, Agua Hedionda Lagoon, Batiquitos Lagoon, San Elijo lagoon, San Dieguito Lagoon, Los Penasquitos Lagoon, Kendall-Frost Reserve, San Diego River, Sweetwater marsh, E Street Marsh, J Street Marsh, South Bay Marine Reserve, and the majority are seen in Tijuana Marsh NWR [2].

List Status

FE, CE

Habitat Affinities

Inhabits coastal marshes, lagoons, and their maritime environments [3] in southern california and northern Baja California, Mexico. Requires shallow water and mudflats for foraging, with adjacent higher vegetation for cover during high water [4 cited from 1]. Nesting habitat includes tall, dense cordgrass and occasionally pickleweed in the low littoral zone, wrack deposits in the low marsh zone, and hummocks of high marsh within the low marsh zone [5].

Taxonomy and Genetics

This rail along with both of the other large rails of the western U.S. has been reclassified taxonomically and renamed by the American Ornithologist Union as the Ridgway’s Rail, Rallus obsoletus [6 cited from 2]. The Light-footed Clapper Rail has been renamed the Light-footed Ridgway's Rail [2].

Seasonal Activity

Activity peaks in early morning and late evening [7;8] when they forage in marsh vegetation in and along creeks and mudflat edges. Often roost at high tide during the day [8].

Life History/Reproduction

Nesting starts in mid-March and extends into August. End of breeding season is typically defined as the end of August, which corresponds with the time when eggs laid during renesting attempts have hatched and young are mobile. Clutch sizes range from 5 to 14 eggs. Both parents share in incubation and rearing [8]. Most egg laying takes places from early April to early May; Chicks will accompany adults on foraging trips by 2 days of age [9].

Diet and Foraging

Omnivorous and opportunistic; forages mostly on salt marsh invertebrates such as beetles, garden snails, California hornsnails, saltmarsh snails, fiddler and hermit crabs, crayfish, isopods, and decapods. 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 [9]. Gleans, pecks, probes, and scavenges from surface [4].

Dispersal

Year-round resident.

Threats

Primary threats include loss and degradation of habitat [2]. Other threats are modification of habitat from dredging actions, changes to tidal influences or siltation, and contaminants from urban runoff. Also threatened with small population size, isolation, automobile strikes, and possible habitat alteration from climate change [1].

Literature Sources