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William S. Birkhead and Charles R. Bennett 



inant vegetation in these areas. As ground elevation increases slightly in 

 the upper reaches of the estuary, the regularly flooded marsh grades 

 into irregularly flooded marsh dominated by Juncus roemerianus (Seneca 

 etal. 1976). 



Carolina Power and Light Company began constructing a nuclear- 

 fueled, steam electric generating plant just north of Southport approxi- 

 mately two years before our study began. This facility was designed to 

 employ a once-through cooling system. The discharge canal for the 

 cooling system was constructed during the summer and fall of 1972, 

 along the northwestern and western edge of the salt marsh bordering 

 Dutchman Creek. This was between 9 and 16 months after our study 

 began. Freshwater runoff from the upper reaches of the bisected tribu- 

 taries and headwaters of Dutchman Creek was diverted into a drainage 

 canal dredged adjacent to the discharge canal (Fig. 1). The drainage 

 canal emptied into the Intracoastal Waterway approximately 1.5 km 

 west of the mouth of Dutchman Creek. Although the hydrographic 

 regime of the lower reaches of the Dutchman Creek estuary was not 

 appreciably affected by the diversion of the freshwater input, salinity 

 increases of between 13 and 15 ppt were recorded in the upper reaches 

 of the estuary below the canal right-of-way and at the mouths of the 

 severed headwaters and tributaries above these canals (Birkhead et al. 

 1977). 



The primary purpose of this paper is to denote the distribution of 

 alligators within the Dutchman Creek estuary before, during, and after 

 its alteration. 



Fig. 1. Map of Dutchman Creek estuary with sampling stations. 



