most winter flounder were impinged, showed even greater (90%) survival. These estimates were similar 

 to those reported for winter flounder at several other power plants (Tatham et al. 1977; MR! 1982). 



One potential problem in returning fish is recirculation and re-impingement, which would increase 

 the probability of mortality. On seven occasions during 1981-83, a total of 299 disc-tagged winter flounder 

 was released near a rock outcrop between Units 1 and 2 (Table 33). Only 15 (5%) fish were impinged, 

 80% of them within 3 d of release. In comparison, 17 fish were later recaptured by the sport and 

 commercial fisheries (4 to 735 d after release). Only once was more than two fish impinged. This occurred 

 after the June 3, 1981 release, when seven of the nine recaptures for this group were made within 2 d; 

 these were the only fish released at night. A small percentage of winter flounder may be susceptible to 

 re-impingement, especially at night or perhaps during storms. However, the Unit 1 sluiceway terminus is 

 farther from the intakes than the centrally located release point. On ebb tides the flow could carry fish 

 away from the MNPS intakes, depending upon their orientation to currents. 



Table 33. Summary of winter flounder tagged and released near the intakes of 



MNPS Units 1 and 2. 



Number recaptured 



Date of Source Number Sport Commercial NUSCo Percent Percent 



release of fish released Impinged fishery fishery trawling* impinged recaptured 



2 June 1981 Trawling 109 1 7 1 7 0.9 14.7 



3 June 1981 Trawling 89 9 1 10 10.1 12.4 

 29 Mar. 1982 Impingement 15 3 1 1 33.3 

 5 Apr. 1982 Impingement 18 1 5.6 5.6 

 12 Apr. 1982 Impingement 8 1 12.5 12.5 

 26 Apr. 1982 Impingement 20 1 2 1 5.0 20.0 

 7 Mar. 1983 Impingement 40 2 2 5.0 10.0 



Total 299 15 13 4 10 5.0 14.0 



All released alive; 3 subsequently recaptured a second time and included in above totals. 



108 



