Of the marine fishes found in 

 freshwater runoff areas, all 77 list- 

 ed (Table 2) were found in ppt 

 salinity waters for extended periods 

 as long as six weeks. As expected, 

 anadromous, catadromous , and diadro- 

 mous fishes such as sturgeon, her- 

 rings, shad, and eels also were 

 abundant in the ppt runoff water 

 zones. Other abundant fishes within 

 the runoff area were the bay anchovy; 

 tidewater and Atlantic silversides; 

 white perch; striped bass; bluefish 

 (young) ; sheepshead (yg) ; pinf ish 

 (yg); black drum (yg) ; striped and 

 white mullet; summer, southern, and 

 windowpane flounders; hogchokers ; and 

 blackcheek tonguefish (Table 2). 

 Thirty-seven of the 77 marine or 

 euryhaline fishes were common to the 

 various disturbed runoff watersheds 

 of the state while only 15 were rare 

 occurrences within these waters. 

 Herrings (9 species), drums (7), and 

 flounders (7) were the dominant 

 groups of fishes captured in the run- 

 off zones. Thirty-five of the 77 

 marine fishes occurred in ppt wa- 

 ters and had not been reported pre- 

 viously by Gunter (1942, 1956). 



Of the fishes encountered with- 

 in the runoff zone, most were small 

 juvenile or one-year-old age class 

 individuals. Some species, such as 

 the drums and flounders, were known 

 to migrate to low salinity nursery 

 waters and hence their presence in 

 the runoff zone could be accounted 

 for by such behaviors (Marshall 1976; 

 Weinstein 1979, 1980). None exhib- 

 ited external signs of stress or ema- 

 ciation as a result of their living 

 in or encounter with the runoff zone. 



The presence or absence of 

 several species within a watershed or 

 the runoff area was also a function 

 of zoogeography (Jenkins et al. 1972; 

 Rohde et al. 1979) rather than run- 

 off or environment, as North Carolina 



lies at the junctures of many coastal 

 north and south ranging species. 

 Like Gunter et a_l. (1974) presence or 

 absence of a freshwater or marine 

 fish in a runoff area was dependent 

 on many other factors, expecially 

 water temperature and oxygen content. 



Water temperatures and oxygen 

 levels, in most areas, of North 

 Carolina were not limiting factors as 

 most runoff occurred during months 

 when water temperatures were low and 

 contained high levels of oxygen (see 

 Schwartz 1973; Schwartz et al. 1979a, 

 b, six-year study of Cape Fear Riv- 

 er) . Whether the varying chemical 

 content of the various watersheds 

 (Geraghty et al. 1973) played a role 

 in the enhancement or demise of a 

 species that was subjected to the 

 sudden runoff waters remains unknown. 



Likewise nutrient change, as a 

 result of runoff, is poorly known for 

 North Carolina waters, the exception 

 being the Neuse River where Hobbie 

 and Smith (1975) noted the effects of 

 runoff on various environmental 

 parameters . 



Nichols (1977), Schubel and 

 Hirschberg (1978), and many others 

 have documented the enormous sediment 

 changes that can occur in a body of 

 water which has been subjected to 

 river floods. Giese et al. (1979), 

 reviewing the hydrology of the major 

 estuaries of North Carolina, noted 

 the effects of sediment "salting out" 

 following freshwater inflow and cal- 

 culated the number of days one could 

 expect upriver portions of major 

 rivers to be drastically affected by 

 this phenomenon. Edgwald (1972) and 

 Griffin and Ingram (1955) reviewed 

 the sediments of coastal Pamlico and 

 Neuse Rivers as a result of runoff. 

 In turn, these sediments most likely 

 caused changes in bottom chemical 

 conditions (Aller 1978) or bottom 



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