The feeding habits of light-footed 

 clapper rails have been examined by direct 

 observation and by dissection of 

 regurgitated pellets. Because crab parts 

 were often found in the pellets of Tijuana 

 Estuary rails, Jorgensen (1975) felt they 

 were an important part of their diet. 

 Observations of Massey and Zembal (1979) 

 suggested a broad diet, including larval 

 and adult insects (beetles, craneflies, 

 and even grasshoppers), spiders, isopods, 

 decapods (ghost shrimp), snails 

 ( Cerithidea californica and Melampus 

 olivaceus ) , crabs ( Pachygrapsus crassipes , 

 Hemigrapsus oregonensis and Uca 

 crenulata ) , crayfish, killifish (Fundulus 

 parvipinnus ) , tadpoles ( Hyla sp.), and 

 even meadow mice (Microtus californicus ) , 

 although the rail's ability to catch mice 

 may be restricted to high tides when mice 

 are stranded or drowned. On occasion 

 rails have been seen to take pickleweed 

 branch tips and to eat pith of broken 

 cordgrass stems. 



The critical factor which limits 

 light-footed clapper rail populations is 

 nesting habitat (Zembal and Massey 1981). 

 Changes in rail density are roughly 

 correlated with the quality and quantity 

 of marsh vegetation. At Upper Newport 

 Bay, rail populations expanded 

 substantially following the 1969 winter 

 storm which broke a dike, restored tidal 

 circulation to the upper bay, and led to 

 the doubling of salt marsh acreage in the 

 wetland. Counts of rails have gone from 

 30 to 35 in 1974 to 196 birds in 1980, 

 many of which were nesting in the newer 

 marsh area. Upper Newport Bay supports 

 the most robust, pure cordgrass marsh in 

 southern California. In contrast, rail 

 populations at Anaheim Bay have declined 

 from a hundred or more (not an actual 

 count) in 1974 to 60 in 1980 and 38 in 

 1981 (Massey and Zembal 1979, Zembal and 

 Massey 1981). This bay has been subsiding 

 in recent decades, perhaps due to oil 

 pumping, and elevations where nests were 

 found averaged 30 cm lower at Anaheim than 

 Upper Newport Bay and Tijuana Estuary. 

 At Los Penasquitos Lagoon, 30 birds were 

 were noted in 1974 and none in 1981. The 

 degree to which these decreases are due to 



migration rather than mortality is 

 unknown. Movements of birds from one 

 wetland to another have not been observed. 

 The bird is a poor flyer, but its sudden 

 appearance at the San Diego River marsh in 

 1981 suggests that it has some local 

 mobility. Attempts to monitor rail 

 movements by banding and telemetry are 

 underway (Zembal and Massey 1981). 



While tall, dense cordgrass is 

 recognized as the preferred rail habitat, 

 other marsh communities have become 

 important in supporting the species, 

 especially following the 1980 flooding. 

 Zembal and Massey (1981) noted a shift to 

 nesting locations in upper marsh habitats 

 at both Anaheim and Upper Newport Bays. 

 In addition, rails have been found to 

 utilize areas of freshwater marsh, when 

 they occur near salt marshes, for feeding, 

 loafing, and escape from high tides. The 

 large marsh at Upper Newport Bay supports 

 the largest number of rails in southern 

 California, but even small marshes can 

 harbor nesting pairs. The small urban 

 marshes near E, F and J Streets in Chula 

 Vista each had a pair of rails in 1981. 



Management plans for this endangered 

 species call for improved and expanded 

 salt marsh habitat. Toward this end, the 

 U. S. Navy has supported marsh enhancement 

 projects at the Tijuana Estuary sewage 

 lagoons (Nordby et al. 1980), and the 

 California Sea Grant College Program has 

 sponsored research for establishing and 

 enhancing marsh vegetation, especially 

 cordgrass (Zedler 1981a). 



Belding's savannah sparrow (Figure 

 48) has been recognized by the State of 

 California as an endangered species 

 species since 1974. Like the rail, it is 

 dependent on salt-marsh habitat, and 

 populations decline when marsh habitats 

 are destroyed. Unlike the rail, it 

 prefers the higher salt marsh habitats, 

 and is particularly abundant in areas 

 dominated by pickleweed ( Salicornia 

 virginica ) . Pickleweed is used for 

 nesting, perching, feeding cover, and as a 

 food source (Massey 1979). 



81 



