growth to a few halophytic species such as saltgrass, glasswort, saltwort, and 

 salt matrimony-wine ( Lycium carol inianum ). 



The coastal grassland or prairie lies further inland and may extend 

 inland 8 to 24 cm (5 to 15 mi) in certain coastal sectors. The coastal grass- 

 lands resemble a mosaic, with the brackish marshes in a discontinuous pattern, 

 frequently along lines of irregular elevation. The gulf cordgrass vegetation 

 type is another stable, edaphic climax system maintained by high soil salinities 

 resulting from irregular brackish or saltwater inundation. Once established, 

 no apparent changes in its composition normally occur, unless disruptive forces 

 such as overgrazing or increased standing water are introduced. Groundsel and 

 marsh elder are two common woody species associated with recently disturbed 

 marsh and coastal prairie sites. These two associates characteristically grow 

 on recent spoil ^-^anks, spoil levees, access canals, and well pads - wherever 

 the substrate has been devegetated and abandoned. 



Other less extensive cover types include some elements of the maritime 

 woodlands, primarily live oak mottes along the northwestern corner of the San 

 Bernard Refugfe. These components appear as the gulf cordgrass system blends 

 into more typically upland systems. Several isolated depressions in the 

 Brazoria Refuge support two or three small fresh marsh systems. The ecosystems 

 are located in the northeast corner of the refuge near Bastrop Bayou. One 

 unique aspect of Brazoria's floristic resources is the presence of one of the 

 '-R system's 174 Natural Research Areas. This unit preserves 70.8 ha (175 

 acres) of southern cordgrass prairie on Christmas Point for future research 

 (USDI, 1975). 



W i 1 d 1 i f e . Withi^ut doubt, the major wildlife attraction of these two refuges 

 ' is the large number of waterfowl, particularly the vast flocks of snow geese 

 that appear each winter. The coastal marshes, ponds, swales, and grain fields 

 provide favorable habitat conditions for large segments of the central flyway's 

 wintering waterfowl population. Personnel of the San Bernard Refuge counted 

 peak populations of 100,000 to 103,000 snow geese and 14,000 to 16^000 ducks, 

 primarily, green-winged teal, shoveler, and American wigeon, during December 

 and January 1976 (USDI, 1976b^,£). The Brazoria Refuge contained similar popula- 

 tion totals and species compositions for ducks, but only about 25,000 to 65,000 

 snow geese for the same period. In 1976, a total of 6,965,370 waterfowl use-days 

 were recorded on the Brazoria Refuge (USDI, 1976b^,£). 



Other avian species of particular interest that frequent the refuge areas 

 are the roseate spoonbill ( Ajaia ajaja ), reddish egret ( Dichromanassa rufescens ), 

 white-tailed hawk ( Buteo albicaudatus ), wood ibis ( Mycteria americana ), and 

 osprey ( Pandion haliaetusT ! Numerous common wading birds, shorebirds, and other 

 wetland associates exploit the diverse array of available habitats, becoming 

 especially abundant wherever a high degree of shoreline/surface-water intersper- 

 sion exists. Here heron, egret, ibis, sandpiper, and others feed primarily on 

 crustaceans, other invertebrates, and fish that inhabit the shallow ponds, 

 sloughs, and wet depressions. 



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