on algae throughout the year, and 

 individuals over 10 cm ate plant material 

 almost exclusively with the composition 

 changing seasonally but including green 

 detritus, pennate diatoms and algae. 

 Topsmelt are rapid swimmers and utilize 

 the entire water column as opposed to 

 gobies and sculpins which are benthic 

 species . 



5.3 HERPETOFAUNA 



Several factors limit the occurrence 

 of reptiles and amphibians in salt 

 marshes. Reptiles require a subterranean 

 refuge and egg deposition sites which are 

 above the high tide line; they cannot 

 burrow in the compacted soils of the upper 

 marsh and hence rely on burrowing mammals 

 for these refuges (Hayes and Guyer 1981). 

 Amphibians require fresh water in order 

 for their eggs to develop, and the 

 temporary nature of southern California 

 streams and pools restricts the time 

 available for aquatic stages. 



The herpetofaunal study of Ballona 

 Wetland (Hayes and Guyer 1981) identified 

 four species which were associated with 

 salt-marsh habitats. The Pacific treefrog 

 ( Hyla regilla ) occurred within pickleweed 

 ( Salicornia virginica ) , but was most 

 common in the bulrushes ( Scirpus sp.), 

 where fresh water is more likely to 

 provide suitable breeding habitat. Two 

 lizards were found in both the pickleweed 

 and salt grass habitats. The southern 

 alligator lizard ( Gerrhonotus 

 multicarinatus ) and the western fence 

 lizard ( Sceloporus occidentilis ) are both 

 widespread species which eat a variety of 

 insects and spiders. The larger and fast 

 moving alligator lizard has also been 

 known to take other small vertebrates as 

 prey. In turn, these lizards are food for 

 snakes, predatory birds, feral cats and 

 dogs. Gopher snakes ( Pi tuophis 

 melanoleucus ) were frequently caught in 

 the areas above tidal inundation and were 

 commonly associated with salt grass 

 ( Distichlis spicata ) . This large (up to 

 1.6 m) and highly mobile snake reportedly 

 feeds on mammals, birds, eggs and other 



reptiles (Hayes and Guyer 1981). The 

 species hibernates and is most active from 

 April to June at Ballona. 



While reptiles and amphibians do not 

 appear to depend on salt- marsh habitats 

 for their existence, the marsh vegetation 

 provides cover and the fauna provides 

 food. Hayes and Guyer (1981) found native 

 vegetation to support more individuals 

 than exotic species, perhaps because fewer 

 insects are associated with introduced 

 plants. 



The least disturbed area of Ballona 

 Wetland supported the largest number of 

 herpetofaunal species and the highest 

 relative densities of three species. This 

 indicates that human activities and urban 

 encroachment may impact reptiles and 

 amphibians . 



5. A BIRDS 



Southern California's coastal 

 wetlands support hundreds of thousands of 

 birds and dozens of species which migrate 

 along the Pacific Flyway. Hence, these 

 areas take on international importance as 

 feeding and resting grounds for species 

 also found from Alaska to Antarctica. 

 Herons, egrets, gulls, terns, shorebirds, 

 ducks, geese, coots, gallinules, and rails 

 can be seen in southern California coastal 

 wetlands throughout most of the year. 

 Even small wetlands (e.g. the 8.1 ha 

 Famosa Slough near Mission Bay) support 

 about MO species of water-related birds, 

 while lists for large areas such as San 

 Diego Bay include nearly 100 species. 

 Habitats where disturbance is less severe 

 support more species than areas which have 

 been highly modified. For example. Dock 

 and Schreiber (1981) found 70 species in 

 the least disturbed portion of Ballona 

 Wetland, while only 32 waterbird species 

 used the adjacent, highly modified area 

 (weedy pickleweed and field habitat) . 

 Similarly, Sully (1977) recorded 60 

 species in the less disturbed Outer Bolsa 

 Chica Bay and only 35 species in 

 Huntington Harbour. Some of the migrants 

 winter in southern California (e.g. 



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