FISHERY BULLETIN: VOL. 71, NO. 2 



Figure 1. — Locations on Georges Bank 

 where winter flounder were collected 

 for age and growth studies. (Dots: 

 eastern Georges Bank; triangles: western 

 Georges Bank.) 



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Locations where samples were taken for the 

 study cover most of the northern half of 

 Georges Bank (Figure 1). Otter trawl catches 

 from the Alhatrosa IV groundfish surveys 

 suggest that there are two somewhat separate 

 areas of winter flounder abundance on Georges 

 Bank. The area of greatest abundance extends 

 from Cultivator Shoal eastward to about long 

 67°W. This is the area where most of the 

 Georges Bank commercial catch is taken. The 

 other area is southwest of Cultivator Shoal 

 and extends westward from there to about long 

 69°W. The two areas are roughly shown by 

 plotting catches of winter flounder from eight 

 groundfish surveys on Georges Bank (Figure 

 2). Although sampling was relatively uniform 

 over the entire Bank to a depth of 200 m (see 

 figures in Grosslein, 1969), catches of five or 

 more winter flounder per otter trawl station 

 were made only in the above-defined areas. 

 Growth was computed separately for fish from 

 these two areas (Figure 2). 



Scales were used for age determination since 

 these appeared easier to interpret than otoliths 

 and had the advantage of greater ease for cal- 

 culation of lengths at earlier ages. The scales 

 were removed from the eyed side of fish along 

 the lateral line in the area just anterior to the 

 caudal peduncle. Total length in millimeters 

 and sex were recorded for each scale sample. 

 Except where noted, lengths given herein are 

 total lengths. 



Impressions of the scales were made in 



Figure 2. — Georges Bank stations (30-min otter trawl 

 hauls) where five or more winter flounder were caught 

 during fall groundfish surveys in 1963-70. (Dashed line 

 indicates the boundary between east and west Georges 

 Bank for the growth study.) 



transparent cellulose acetate strips. These were 

 viewed with a microprojector using 40 X 

 magnification, and year marks (annuli) were 

 identified and counted. Criteria for distinguish- 

 ing annuli were the same as those used for 

 New England yellowtail flounder, Limanda 

 ferruginea, (Lux and Nichy, 1969) which, like 

 the winter flounder, have ctenoid scales. With 

 the exception of the first year, spring and 

 summer growth was characterized by widely 

 spaced circuli (rapid length accretion) and 

 fall and winter growth, by closely spaced 

 circuli (slow length accretion). The outer edge 

 of the zone of closely spaced circuli was con- 



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