39 



Chesapeake Bay's Submerged Aquatic Beds 



Situated in eastern Maryland and Virginia, Cliesapeake 

 Bay is the largest estuary in the United States. Many 

 rivers drain into the Bay including the Susquehanna, Po- 

 tomac, Patuxent, James. York and Chester (Figure 35). 



The Bay once represented the primary overwintering 

 area for canvasback ducks which fed on submerged 

 aquatic vegetation (Figure 36). Fifty percent of the Atlan- 

 tic Flyway population of canvasbacks were found in the 

 Bay region (Stevenson and Confer 1978). While still 

 among the more important overwintering areas for can- 

 vasbacks, Chesapeake Bay is the single most important 

 wintering ground in North America for whistling swans 

 (Bellrose 1976). Canada geese and black ducks also use 

 the Bay area in winter. Aquatic grass beds provide 

 spawning areas forestuarine-dependent fishes like striped 

 bass, shad and herring and offer shelter for their young. 

 Important submerged plants include pondweeds, redhead 

 grass, eelgrass, wild celery, waterweed. naiads, musk- 

 grasses and Eurasian milfoil. 



Sea grass beds in the Bay have been declining since the 

 1960's. According to a recent study (Stevenson, et al. 

 1979) in Maryland, submerged aquatic vegetation de- 

 creased by almost 65% from 1971 to 1978. A similar 

 decline has also been observed in Virginia waters. At the 

 mouth of the Susquehanna River, submerged grasses at a 



Susquehanna River 



PENNSYLVANIA 



Potomac River 



Rappahannock 

 River 



Pocomoke River 



Fig. 35. Chesapeake Bay and its major tributaries. 



IfW* 



Fig. 36, Chesapeake Bay is one of the more important wintering areas for canvasbacks in North America. 



