glasswort. Hightide-bush grows in narrow 
bands on the more elevated natural levees of 
the tidal creeks or guts and on the spoil 
banks of drainage ditches; it grows in fairly 
broad zones along the upland margins of the 
marshes, often associated with groundselbush, 
waxmyrtle, bayberry, and other shrubs. Sea- 
lettuce is common at the mouths of tidal 
creeks. Some widgeongrass usually is present 
in marsh ponds with poor drainage, and is 
fairly abundant in certain artificial ponds 
impounded by gut plugs ordams. Small pockets 
of brackish or fresh estuarine marsh occur 
along the mainland side of the coastal embayed 
marshes near the upper limits of tide water, 
where small streams drain into the marsh. 
The more important plant species in these 
restricted areas include Olney three-square, 
common three-square, big cordgrass, and 
rosemallow, 
Fishes and Invertebrates 
Numerous small fish of various species 
inhabit the coastal embayed salt marshes. 
Good-sized schools of broad _ killifish 
(Cyprinodon variegatus), striped killifish (Fundulus 
majalis),and common killifish (Fundulus heteroclitus) 
abound in the creeks or ponds. Among the 
invertebrates, saltmarsh snails (Melamms 
bidentatus) and periwinkle snails (Littorina irrorata) 
are common and widespread. Clusters of ribbed 
mussels (Volsella demissa) are frequent along the 
margins of tidal creeks and guts. Swarms of 
fiddler crabs (Uca pugnaz) and fair numbers of 
marsh crabs (Sesarma reticulatum) are present 
on the tidal mud flats, along with numerous 
amphipod, copepod, and shrimp-type decapod 
crustaceans. 
Waterfowl . 
The characteristic species of transient and 
wintering waterfowl are: 
Primary Species 
Canada Goose Black Duck 
Secondary Species 
Shoveler 
American Widgeon 
Hooded Merganser 
American Coot 
Snow Goose 
Mallard 
Pintail 
Green-winged Teal 
Blue-winged Teal 
(transient) 
Black Ducks are the only common and widely 
distributed waterfowl. Canada Geese are nu- 
merous only in a few local areas. 
Black Ducks, Mallards, and Green-winged 
Teal generally are most numerous along the 
tidal creeks and guts. Canada Geese and Snow 
Geese are most numerous on the more ex- 
tensive saltmarsh cordgrass areas or on tidal 
mud flats. Pintails, Shovelers, Blue-winged 
13 
Teal, and American Widgeons prefer the 
open marsh ponds with poor drainage, or ponds 
with stable water level that have been created 
artificially. 
Scattered pairs of Black Ducks breed on the 
coastal embayed salt marshes, and occasion- 
ally a pair or two of Mallards or Blue-winged 
Teal. Isolated islands of marsh in the coastal 
bays apparently are more attractive for nest- 
ing than the marshes along the shore. All 
nests found were in the drier, more elevated 
portions of the marsh. 
Sample boat counts of waterfowl made on 
March 2, 1955, and on December 27, 1955, 
covered approximately 2,875 acres. A total 
of 1,919 waterfowl was recorded, a density 
of about 430 birds per square mile. Canada 
Geese made up more than one-third of the 
total, and Black Ducks made up another third, 
The gullet and gizzard food contents of nine 
waterfowl collected in the coastal embayed 
salt marshes were examined. Commonest 
plant foods were seeds of Olney three-square, 
common three-square, and widgeongrass. The 
saltmarsh snail (Melampus bidentatus) was the 
predominant food item taken by the six Black 
Ducks examined, 
Canada Geese and Snow Geese were ob- 
served to feed to a considerable extent on the 
leaves and rootstalks of saltmarsh cordgrass 
as well as on corn and grain sprouts in fields 
nearby. 
SALT ESTUARINE BAY MARSHES 
The salt estuarine bay marshes (fig. 3) 
occupy approximately 113,000 acres. They 
include the large off-shore islands (Bloods- 
worth, South Marsh, Smith, and Tangier Is- 
lands) as well as the outer fringe of marsh 
along the bay shores of Dorchester and Somer- 
set Counties, Maryland, and adjacent portions 
of Virginia. Salinity is high and tidal fluctua- 
tions are narrow. j 
Vegetation 
The more characteristic plants of salt 
estuarine bay marshes are: 
Primary Species 
Widgeongrass Saltmarsh Bulrush 
Saltgrass (local) 
Saltmarsh Cordgrass Needlerush 
Saltmeadow Cordgrass Hightide-bush 
Secondary Species 
Fimbristylis Sea-lavender 
(F. castanea) Seaside Goldenrod 
Blackrush Aster 
Atriplex (A. tenuifolius) 
Glasswort Groundselbush 
(Salicornia europaea) Saltmarsh Fleabane 
Saltmarsh Mallow 
