temperatures were attained in Zones 2, 3, and 4 

 during August (27.9°-29.1°C) and in Zones 5 

 and 6 during September (29.1° and 29.6°C). 



FISH DISTRIBUTION AND 

 SALINITY 



One hundred and four species of fishes, rep- 

 resenting 50 families, were collected during the 

 surveys (Table 3). From 22 to 26 species were 

 taken in each of the three zones in the upper 

 river, while in the lower river numbers of spe- 

 cies increased in relation to distance down- 

 stream; 53 species were collected from Zone 4, 

 57 from Zone 5, and 69 from Zone 6. Seventeen 

 species were collected in the upper river exclu- 

 sively, and 64 species were confined to the lower 

 section of the river; the remaining 23 species 

 ranged over both sections of the river or were 

 found throughout the entire system during some 

 stage of their life cycle. 



Thirteen of the 17 species exclusive to the up- 



per river were collected in freshwaters only, 

 0.0-0.5/^f salinity, while four species (longnose 

 gar, Lepisostetis ossetis; golden shiner, Notemig- 

 onus crysoleticas; white catfish, Ictalurus cattcs: 

 and black crappie, Pomoxis nigromaculatiis) 

 showed a tolerance for low salinity or brackish 

 waters, 0.6-10'.^f. The longnose gar is a well- 

 known invader of moderate to high salinity 

 waters, but was not taken in the Newport River 

 estuary. Of the 13 species taken only in fresh 

 waters, three are known to occur in saline waters, 

 but their scarcity in the collections reflected a 

 freshwater distributional pattern. They were 

 the anadromous American shad, Alosa sapidis- 

 sima, and white perch, Morone amencana, and 

 the marsh killifish, Fuvdulus confluentus. Con- 

 sequently, only 10 species were regarded as 

 strictly freshwater forms. 



The fish population of the lower river or estu- 

 ary was essentially a marine fauna. The only 

 species of freshwater origin collected in the estu- 

 ary were gizzard shad, Dorosoma cepedianum, 

 and the catadromous American eel, Anguilla 



Table 2. --Mean monthly salinities and temperatures in each zone of the Newport River during periods 

 of actual biological sampling. Lines denote arbitrary divisions of fresh water (0.0-0.5°/oo) 

 and low (0.6-10°/oo) , moderate (10-25 °/oo), and high (>25°/oo) salinity. 



Month 



Zone 



Month 



Zone 



