Broadly viewed, the study revealed similarities between the 

 terrestrial invertebrate communities of the Oregon marshes and 

 those studied elsewhere on the Pacific and Atlantic coasts. The 

 full extent of this similarity can not be assessed since the level 

 of identification varied among the studies. The Oregon marsh study 

 did not study seasonality or identify immature insects collected 

 from exposed vegetation. However, the data provide a sufficiently 

 accurate picture of community structure and aquatic food chains for 

 comparison with, other marsh communities. In these comparisons, the 

 collection method is discussed in relation to the part of the 

 community represented. 



The invertebrate fauna of the level marsh, debris line, pan, 

 tidal creek, and tidal flat habitats are summarized in Tables 6 

 and 7. The tables include animals captured by all sampling methods 

 used in each of these habitats. Taxonomic diversity of the level 

 marsh habitats was highest in the high level marsh, slightly lower 

 in the low level marsh, and lowest in the debris line (Table 6) . 

 However, the habitats share several taxa. A similar overlap occurred 

 in fauna of aquatic habitats (Table 7) . Composition of the tidal 

 creek infauna is similar to that of the muddy tidal flat. Taxa 

 from this community also appear in tidal pans. More extensive 

 sampling of pans, especially in the low marsh, would probably 

 reveal greater similarities of pan and creek faunas than indicated 

 here. 



The fauna of the Oregon marsh soils, dominated by oligochaetes 

 and dipterous larvae (Fig. 3), are not diverse partly because samples 

 were collected during the winter and early spring when some insect 

 species presumably rest in the egg state. The high abundance of 

 oligochaetes and near absence of polychaetes contrasts with Cammen's 

 1976 results on macroinvertebrates of natural and planted salt 

 marshes in North Carolina. In the natural marshes and at one bare 

 soil site, polychaetes dominated (by biomass) , while insect larvae 

 and amphipods were dominant in some planted and bare soil sites. 

 Composition of the marsh and creek polychaete fauna was similar. 

 Among the several dipterous families Cammen lists, only Dolichopodidae 

 was abundant in the Oregon marsh soils. High densities of Cera- 

 topogonidae and Chironomidae occurred in the Oregon marshes and 

 were sparse or absent from the North Carolina marshes. Both the 

 North Carolina and Oregon lists are relatively short in comparison 

 to Wall's (1973) list of taxa for Cape Cod marshes. Thus more 

 extensive collections might show greater similarity between 

 Atlantic and Pacific coast soil infauna. 



The low vegetation was inhabited by dense populations of Acarina 

 and, in high marshes, moderate populations of Collembola (Fig. 4). 

 Acarina, Homoptera, and Diptera were the most abundant invertebrates 

 in the high vegetation. Lane (1969) also found Homoptera and Diptera 

 the dominant insect orders in the San Francisco Bay marsh. He 

 collected by sweep net, aerial net, and blacklight, so his collections 

 were most similar to the sweep net collections of high vegetation in 

 this study. Cameron ri972) , who also studied a San Francisco Bay 



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