396 



Fishery Bulletin 101(2) 



PAMLICO SOUND 



upper 



Figure 9 



Mean catch per unit of effort for Atlantic croaker in general areas of the 

 Cape Fear and Pamlico Sound, NC, estuaries by sampling week, March- 

 June 1987. Vertical bars represent plus and minus one standard error of 

 the mean. The .v-axis labels (from left to right) stand for March, April. April, 

 April, May, May, June. 



areas had similar instantaneous mortality rates (analysis 

 of covariance, P>0.05). Upper Cape Fear Atlantic croaker 

 exhibited significantly lower mortality rates than those in 

 the lower Cape Fear (P<0.0,5). All Atlantic croaker mortal- 

 ity rates in the Cape Fear were significantly higher than 

 those in the Pamlico. Daily mortality rates for Atlantic 

 croaker in the upper and lower Cape Fear were 2.96 %/d 

 and 3.73 %/d, respectively and in the upper and mid-lower 

 Pamlico were 0.90 and 0.80 ^r/d, respectively. 



Discussion 



Primary nursery area habitats in two different estuaries 

 were not equally valuable for spot and Atlantic croaker. 

 Considered together, growth, mortality, and distribution 

 data indicated that upstream oligohaline creeks provided 



the best environment, followed closely by downstream 

 polyhaline areas. In all regards, the middle reaches of 

 the estuary appeared to be less valuable (or at least less 

 used). These consistent results for both species in the two 

 separate estuarine systems lend support to their general 

 applicability. Other studies were marginally useful in 

 evaluating these results because of their lack of synoptic 

 comparisons across a wide variety of habitats and because 

 of limitations in or lack of growth and mortality data for 

 estuarine juveniles of these species. 



The main evidence that oligohaline habitats provided 

 better environments than polyhaline areas was that spot 

 (both systems) and Atlantic croaker (in Cape Fear) exhib- 

 ited significantly lower mortality in the freshwater PNAs. 

 Miller et al. ( 1985) reported lower mortality for these spe- 

 cies in mesohalino areas compared to high salinity areas 

 of Pamlico Sound. In the Cape Fear River, Weinstein and 



