Winter Flounder 



The results in this section are based on data from Ex- 

 periments One, Two, and Four, representing a total catch of 

 4,152 winter flounder. There were insufficient data to 



Table 19. — Winter flounder selection factor summary. 





Total 

 no. of 





Selection factor 





Small 



Large 



Alternate 



Experiment 



fish 



mesh 



mesh 



tow 



One 



725 



2.07 



2.23 



_ 



Two 



2,398 



2.02 



2.05 



2.21 



Four 



1,029 



— 



— 



— 



Combined 



4,152 



2.04 



2.07 



2.27 



Table 20. — Winter flounder length frequency 

 distributions and percent retained for the small- 

 mesh (103 mm overall average) covered tows — six 

 vessels. 



Length 



Numbers caught 





interval 





103 mm 



Percent 



(cm) 



103 mm 



plus covers 



retained 



10-12 











0.0 



13-15 



1 



9 



11.1 



16-18 



3 



11 



27.3 



19-21 



10 



30 



33.3 



22-24 



96 



109 



88.1 



25-27 



161 



170 



94.7 



28-30 



204 



209 



97.6 



31-33 



161 



164 



98.2 



34-36 



83 



84 



98.8 



37-39 



68 



68 



100.0 



4f>42 



70 



70 



100.0 



43-45 



46 



46 



100.0 



4^48 



24 



24 



100.0 



49-51 



15 



15 



100.0 



52-54 



2 



2 



100.0 



55-57 



2 



2 



100.0 



58-60 



1 



1 



100.0 



Totals 



947 



1,014 





calculate the selection factors from the uncovered tows in Ex- 

 periment One and from both covered and uncovered tows in 

 Experiment Four. However, with all data combined, fairly 

 good results were obtained (Tables 19 to 21, Fig. 12). There 

 again is an increase in selection factor with the larger mesh. An 

 overall selection factor of 2.2 for winter flounder seems a 

 reasonable choice based on this data. The 25-75 % selection 

 range was in most cases about 5 cm. 



From the uncovered-tow data (Table 22) there seems to be 

 an increase in efficiency for the larger mesh starting at about 



Figure 12. — Selection curves — winter flounder. Solid circles = 133 mm 

 covered; open circles = 103 mm covered; open triangles = 133 mm uncovered. 



Table 21. — Winter flounder length frequency 

 distributions and percent retained for large-mesh 

 (133 mm overall average) covered tows — six vessels. 



Table 22. 



■ Winter flounder length frequency distributions and percent retained 

 from uncovered cod end tows — six vessels. 



Length 



Numbers caught 





interval 





133 mm 



Percent 



(cm) 



133 mm 



plus covers 



retained 



10-12 











0.0 



13-15 







6 



0.0 



16-18 



1 



45 



2.2 



19-21 



9 



107 



8.4 



22-24 



17 



120 



14.2 



25-27 



58 



158 



36.7 



28-30 



145 



241 



60.2 



31-33 



127 



155 



81.9 



34-36 



86 



92 



93.5 



37-39 



54 



56 



96.4 



4042 



58 



59 



98.3 



43^t5 



51 



51 



100.0 



46-48 



19 



19 



100.0 



49-51 



16 



16 



100.0 



52-54 



11 



11 



100.0 



55-57 



6 



6 



100.0 



58-60 



3 



3 



100.0 



61-63 



1 



1 



100.0 



Totals 



662 



1,146 













°Io retained by 



Length 









133 mm 



interval 



Numbers caught 



B 

 A 



B x 100 



(cm) 



(A) 103 mm 



(B) 133 mm 



1.24 



10-12 











0.00 



0.0 



13-15 











0.00 



0.0 



16-18 











0.00 



0.0 



19-21 



16 







0.00 



0.0 



22-24 



115 



10 



0.08 



7.2 



25-27 



204 



30 



0.15 



12.3 



28-30 



265 



99 



0.37 



31.1 



31-33 



168 



148 



0.88 



73.4 



34-36 



90 



185 



2.06 



171.3 



37-39 



85 



106 



1.25 1 



103.9 



40-42 



103 



113 



1.10 | 



Avg. 91.4 



43^(5 



62 



65 



1.05 



1.2 87.4 



46^18 



32 



43 



1.34 J 



110.1 



49-51 



8 



16 



2.00 



166.7 



52-54 



6 



13 



2.17 



180.6 



55-57 



3 



6 



2.00 



166.7 



58-60 



1 







0.00 



0.0 



Totals 



1,158 



834 







15 



