worldwide genus is still unsettled, and 

 geographic distributions are hence 

 uncertain. Other genera that have been 

 collected in salt marshes include Agonum . 

 C alathus and Bradycellus . 



Tiger beetles of the genus Cicindela 

 ( Cicindelidae) are common insects on 

 coastal mud and salt flats. The eggs, 

 larvae and pupae are subterranean, while 

 the adults are highly active terrestrial 

 predators. Among their prey are the 

 abundant kelp and brine flies, which are 

 often nuisances to beach-goers. Some 

 species are useful indicators of 

 environmental quality (Nagano 1981 and in 

 press, Nagano et al. 1981). C. 

 hirticollis gravida , C. gabbi and C. 

 latesignata are able to survive only in 

 localities that have not been impacted by 

 excessive recreation, urban expansion or 

 other human disturbances. 



This section discusses only a minute 

 fraction of the coastal salt- marsh insect 

 fauna. Their large numbers of species, 

 importance in food chains and potential 

 value as indicators of undisturbed marsh 

 habitats suggest a great need for further 

 study. Clearly, any attempt to describe 

 salt marsh ecosystems thoroughly must 

 include the insect components. 



southern California marshes differ 

 substantially from eastern marshes, and 

 the reader should begin to be skeptical 

 about extrapolating conclusions about the 

 role of wetlands in supporting fishes. As 

 it turns out, the southern California 

 marshes and tidal creeks are utilized by a 

 large number of fish and invertebrate 

 larvae, and the composition bears some 

 resemblance to east coast wetlands. But 

 only a single study has directly 

 investigated the role of marshes in 

 comparison with offshore habitats (Nordby, 

 in prep.). 



Much of the research conducted on 

 coastal wetland fishes has emphasized 

 adult and juvenile forms collected from 

 bays and deep channels. Studies of fish 

 larvae and eggs from these deeper water 

 habitats are somewhat less numerous. Fish 

 utilization of tidal creeks and the 

 associated salt marsh habitat is least 

 well known. Allen (1980), Dickert et al. 

 (1981) and Swift and Frantz (1981) provide 

 data on juveniles and adults in shallow 

 channels, but only Nordby (thesis in 

 progress) and Swift and Frantz (1981) 

 investigated larval and egg densities 

 within marsh tidal creeks in southern 

 California. 



5.2 FISH 



Southern California wetlands are 

 often reported to be essential nurseries 

 for commercially important fish, which in 

 turn depend on productivity of marsh 

 vegetation. Such statements derive from 

 work on the East and Gulf coasts of the 

 United States, and conclusions are often 

 transferred (without critical evaluation) 

 to wetlands of the Pacific Coast. By now 

 it should be obvious that many of the 

 physical and vegetational features of 



This section was researched by Chris 

 Nordby, M. S. student, San Diego State 

 University. 



Tidal Creeks and Marsh Utilization 



The smaller tidal creeks found within 

 salt marsh vegetation provide habitat for 

 a number of smaller fish species, as well 

 as eggs and larvae of larger fish. Fish 

 collected within tidal creeks probably 

 move within the marsh vegetation during 

 high tides, and at least one species, the 

 California killifish ( Fundulus 

 parvipinnis , Figure Ml), appears to 

 utilize the marsh in preference to creeks 

 and channels. 



Nordby (in prep.) sampled eggs and 

 larvae of tidal creeks (2-3 m wide, <1 m 

 deep) at Tijuana Estuary (Table 12). The 

 larval dominants were silversides 

 ( Atherinidae) , the longjaw mudsucker 

 (Gillichthys mirabilis) and the northern 

 anchovy ( Engraulis mordax ) . A goby 



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