A wide variety of organisms are found in and around the intertidal emergent 

 salt marsh because of its high productivity. The consumers in the salt marsh 

 are herbivores (organisms that consume algae and green plants), detritivores 

 (organisms that consume dead plant and animal particles as their chief source 

 of nutrients), and the predators (organisms that actively search for prey). 



Invertebrate communities in salt marshes are dominated by the hard-shelled 

 bivalves or shellfish, gastropods (snails), crustaceans, and soft-bodied worms 

 or polychaetes. 



Invertebrates are a primary source of food for higher consumers. Data on the 

 nature of the invertebrate population of the Maine salt marshes are scarce. 



Unfortunately little is known about the population dynamics, distributions and 

 life histories of benthic invertebrates in the intertidal salt marshes in 

 Maine. In a Cousins River, Yarmouth, salt marsh, the benthic mud-dwelling 

 invertebrates of the intertidal marsh are dominated by the deposit- and 

 suspension-feeding annelids (segmented worms), particularly the oligochaetes 

 (Larsen, unpublished ) . Bivalves include the deposit feeding baltic clam and 

 the filter-feeding soft-shelled calm. Gastropods are represented by the rough 

 periwinkle and the common mud snail. The crustaceans are represented by the 

 isopod Edotea triloba and amphipod Orchestia grillus (Larsen, unpublished ) . 



The presence of forage fish in salt marshes is one of the primary reasons that 

 the larger commercially important carnivorous species at sometime in their 

 life history utilize wetland areas to feed. Small fishes inhabiting the 

 intertidal wetlands, such as the ubiquitous mummichog and the silverside, are 

 preyed upon continually by striped bass, winter flounder, and eels. Small 

 fish that feed in the marsh during high tides represent an integral link in 

 the estuarine food web between the primary producers and the higher consumers. 

 Intertidal wetlands are also valuable nurseries for larval and juvenile fishes 

 (see chapter 11, "Fishes," for more detailed information). 



Small mammals that frequent the marsh are the meadow mouse and the muskrat. 

 Muskrats not only consume the leaves and stems of cordgrass and bulrush 

 ( Scirpus spp.) but then also use the grass blades for hutch building. Upland 

 species that occasionally comb the marsh in search of food are raccoons, 

 opposums , and woodchucks. Weasels, red and gray foxes, deer, and rabbits, 

 also frequent the emergent marshes. They utilize the marshes for food and 

 sometimes are preyed upon by other animals. 



Nixon and Oviatt (1973) reported occasional small mammals including mice, 

 voles, muskrats, and raccoon in Bissel Cove salt marsh in Rhode Island. The 

 impact by small mammals on salt marsh systems was considered slight, except 

 for the building of hutches by muskrats. No studies to date have described 

 the use of the intertidal salt marsh by small mammals in Maine. 



Various waterfowl, shorebirds, wading birds, and terrestrial birds inhabit the 

 low cordgrass marsh, where they find food and cover. Red-winged blackbirds 

 and sharp-tailed sparrows consume cordgrass seeds. Both black ducks and 

 green-winged teals eat the root and rhizomes of cordgrass, although they 

 prefer the invertebrates in the associated bottom materials seasonally. Black 

 ducks and mallards consume mud snails found in wetlands. Geese consume the 

 leaves and stems of cordgrass and feed extensively on bulrush when it is 



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