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of the marshes. Near the mainland (southwest of the Thorofare) 

 and near Cedar Island (northeast of the John Day Ditch), 

 there are extensive areas of fairly pure stands of Juncus 

 roemerianus . 



In this report, we are concerned with only the marshes. 

 However, there are also several maritime shrub thicket 

 hammocks on the edges of the marshes, which we did not visit. 

 One of these, Rumley's Hammock, covers several acres and 

 might be of special interest. 



Physical Features: 



These marshes are essentially level. Lunar tides in 

 this area are very slight and the marshes are flooded only 

 by the tides of tropical cyclones or by the most 

 extreme wind tides. According to Mixon and Pilkey (1976), 

 the marshes are part of a "thin veneer of Holocene 

 saltmarsh peat, mud and sand" that lie on "silty and 

 clayey sand of Pleistocene age". 



Rare Plants and Animals: 



Plants: none 



Reptiles: Water snakes ( Natrix spp.) are common in 

 these marshes. Specimens here are probably 

 referable to Natrix sipedon williamenglesi , 

 which was considered by Bruce et al. (in Cooper, 

 J.E., S.S. Robinson, and J.B, Funderburg (Eds) 

 1977) to be of undetermined status, i.e. the _ 



population is deserving of concern but the lack 

 of information makes it impossible to assign it 

 to the proper category of concern. 



Birds: We list rare birds in two categories: 



1) those directly associated with the marshes 

 and associated pond holes, 



2) those occurring only on the adjacent waters 

 and along the marsh-forest border or those that feed 

 above the marshes. 



Evaluation of the Site's Ecological Significance: 



1) The Cedar Island Marshes are one of the largest 

 contiguous tracts of irregularly flooded salt marsh in 

 the state. They are probably the largest tract of such 



marsh in the state that contains a significant amount of i 



Spartina patens . ^ 



2) ^The Cedar Island Marshes are relatively unaltered. 

 Elsewhere in the county, most irregularly flooded marshes 

 have been subjected to ditching for mosquito control, 

 especially the more extensive marshes (as just southwest 

 of Davis). Post and Enders (1969) suggested that ditching 

 of salt marshes may be harmful to some species of birds. 



