ECOLOGY OF BUZZARDS BAY: An Estuarine Profile 61 



headwaters are fresh or brackish, stands of reeds 

 and cattails predominate at the landward edges of 

 the wetlands. Although few animals live or burrow 

 in the sediments of the high marsh zone, the historic 

 utilization of salt hay as feed and fodder for animals 

 and more recently its use as a weed-free garden 

 mulch have focused attention on the value of these 

 wetlands as a usable resource for almost four cen- 

 turies. 



Marine life is abundant in the salt marshes of 

 Buzzards Bay, such as snails, crabs, mussels, am- 

 phipods. and large numbers of small fish. Many 

 species of birds (wrens, rails, and wading birds; 

 Fig. 4.8) feed on the fish and invertebrates, while 

 others (Canada goose (Branta canadensis) and 

 snow goose {Chen caerulescens); Teal 1 986) feed 

 on marsh plants. Mammals such as voles, field mice, 

 raccoons (Procyon lotor), and skunks (Mephitis 

 mephitis) forage in the marsh during low tides. 

 Marshes are well known for their abundance of 

 mosquitoes and biting flies, and great efforts are 

 undertaken through management practices, such as 

 ditching, to limit the habitat (primarily stagnant pools) 

 required for breeding. Although considered a nui- 

 sance to humans and potentially carriers of diseases 

 such as encephalitis, these insects provide substantial 



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Fig. 4.8. The great egret {Casmerodius albus) Photo 

 by B Howes. 



food for birds and surface-feeding fish in the wet- 

 land ecosystem. Other insects such as plant hop- 

 pers, grasshoppers, and aphids, as well as many 

 species of amphipods and spiders, also are an im- 

 portant part of the fauna of Buzzards Bay salt 

 marshes. 



Molts of the horseshoe crab (Limulus 

 polyphemus) and frequently the crab itself, are com- 

 mon sights around Buzzards Bay. Known as a "liv- 

 ing fossil," horseshoe crabs have remained basi- 

 cally unchanged over the past 200 million years, 

 with ancestors estimated to have roamed shore- 

 lines roughly 350 million years ago. Not actually a 

 crab at all, Limulus is an arthropod, related to spi- 

 ders and scorpions. The larger females move from 

 deeper water in early summer to lay eggs along the 

 high tide line. Horseshoe crabs are particularly in- 

 teresting in that they possess a blue, copper-based 

 blood with only one type of cell, which can be ex- 

 tracted for use in various medical assays such as 

 identification of infections caused by spinal menin- 

 gitis and E. coli, as well as certain types of cancers 

 and blood clots. 



Fish are an important part of the ecology of 

 Buzzards Bay salt marshes, and as both predator 

 and prey they represent an important component 

 of the estuarine food web in the marsh-bay system. 

 The tidal marshes of Buzzards Bay support resi- 

 dent species, which spend most of their life within 

 the tidal creeks and pools of the marsh system, and 

 nonresident or invading species, which enter into 

 marsh waters and spend only a portion of their life 

 there. Of the nonresident species, some are adults 

 that enter into salt marshes to spawn, and others 

 are juveniles of coastal species that use the marshes 

 as nursery grounds. 



The resident species offish found in Buzzards 

 Bay salt marshes are typified by the Atlantic silver- 

 side, the four-spined stickleback, and three spe- 

 cies of killifish, mummichog, striped killifish, and 

 sheepshead minnow (Cyprinodon variegatus). 

 Spawning in the marsh, most of these fish are active 

 from April through October and then move out of 

 the marsh into deeper water or burrow into the 

 bottom of tidal creeks or pools during winter. The 



