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The salt marshes of California have undergone significant changes in the last century. The increased human population in California has reduced the viability of salt marshes by elimination or reduction of fresh water input, reduction of tidal flush, introduction of exotic predators, increased anthropogenic contamination, and a reduction in the total number of marshes Goodbred et al., 1996. The lightfooted clapper rail Rallus longirostris levipes is believed to have been common in salt marshes and has an historical range extending from Santa Barbara County, California, to northern Baja California, Mexico Grinnell et al., 1918. Its diet is known to consist primarily of invertebrates various crab species, California horn snail, Cerithidea californica, but softer material like vegetation, spiders, and insects that are not detectable in its regurgitated pellets may also be part of its diet Jorgensen, 1975. They also take small 24 cm intertidal fish Ledig, pers. obs. The lightfooted clapper rail is listed as an endangered species by both the federal and the California State governments US Fish and Wildlife Service, 2001; California Department of Fish and Game, 2001. Because of concern about contamination impacts on rail populations, we collected samples of addled rail eggs, crabs, and sediment from the salt marshes at Seal Beach National Wildlife Refuge in Orange County and Tijuana Slough National Wildlife Refuge in San Diego County, both in southern California. Previous analyses for organic contaminants showed no evidence that either organochlorine pesticides primarily DDT metabolites or polychlorinated biphenyls were affecting reproductive output of the lightfooted clapper rail at Seal Beach or Tijuana Slough marshes Goodbred et al., 1996. Our tests for inorganic analytes, however, show potential threats from Cr and Cu, both from possible anthropogenic sources.