Wildlife . The Delta Refuge is one of the principal wintering areas for 

 geese and ducks. Snow, Canada, and white-fronted geese ( Anser albifrons ) 

 prefer the flats and pass forks, which usually harbor dense growths of three- 

 square and other emergents. Wigeon, gadwall, pintail ( Anas acuta ), shovelers, 

 and teal arrive in the fall and feed on vegetation in and near the open ponds. 

 The mottled duck ( Anas fulvigula ) is a year-round resident. 



In the warmer months, many species of wading and shorebirds inhabit the 

 refuge. Herons, egrets, ibises, and sandpipers are abundant. Bitterns, 

 gallinules, and rails nest in the rank vegetation of levee banks. 



The system of branching levees also supports a considerable number of 

 mammals, including white-tail deer, raccoon, swamp rabbit, and opossum. Nutria, 

 mink, muskrat, and otter are the important furbearers found on the refuge. 

 The nutria, released near the refuge in 1950, require annual removal by local 

 trappers in order to keep the population in check. 



The open ponds of the refuge are commercially fished for garfish, catfish, 

 and buffalo. Other freshwater fish include shad, crappie, and bass. Brackish 

 and salt waters near the Gulf of Mexico contain typical estuarine fish: mullet, 

 porgy, croaker, flounder, trout, shrimp, and crab. 



Sabine National Wildlife Refuge 



The Sabine Refuge is the second of two that were selected as study sites 

 in Louisiana for the determination of ecological effects of oil and gas activi- 

 ties in coastal wetland systems. The following is a discussion of the ecosystems 

 present and provides a description of the environmental setting in the Sabine 

 NWR. 



Location . Sabine NWR is located in the southwestern corner of Cameron 

 Parish, Louisiana, and occupies more than 56,680 ha (140,000 acres). The refuge 

 is bound on the north by cultivated fields (rice) and marsh; on the south by 

 pasture lands and coastal redges; on the east by Calcasieu Lake; and on the 

 west by Sabine Lake and the Texas-Louisiana state border. Approximately nine 

 km (five mi) separates the Gulf of Mexico from the souther boundary of the 

 refuge. The refuge headquarters are located on State Highway 27 about 11 km 

 (7 mi) south of Hackberry, Louisiana. Delta NWR, the other study site chosen 

 in Louisiana, is about 400 km (250 mi) to the east. 



Geology . The substrate of the Sabine Refuge is a relatively thin veneer 

 of recent sediments. It was deposited on sands, silts and clays, which were 

 lain down in the gulf coast geosyncline during the Cenozoic period. The 

 Cenozoic, lasting 70 million yr, witnessed many marine transgressions and 

 regressions (Williamson, 1959). However, sea level has maintained its relative 

 position for thousands of yr. During this time, the various distributaries 

 of the Mississippi River shifted position, providing material which was carried 

 laterally by longshore currents to form marsh, tidal flat, and bay deposits. 



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