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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Figure 5. — Distant recaptures of yellowtail flounder released off No Mans Land (Nos. 4 and 10), 



(Nos. 5 and 11) and off Nauset Beach (Nos. 9 and 12). 



Nantucket Shoals 



were winter returns from summer releases, and 

 Clyde C. Taylor has suggested that they indicate 

 a seasonal migration from Georges Bank to the 

 southern New England grounds in the winter 

 time. There was also one winter return from 

 southwestern Georges Bank. It would be con- 

 sistent with the returns from this one experiment 

 to postulate a summer population on Georges 

 Bank which moves westward to the southern New 

 England grounds in the winter. Such an east- 

 west migration would be similar to the seasonal 

 movements already noted for the releases south of 

 Long Island. It appears unlikely that such a 

 seasonal migration involved many fish during the 

 peak years of the fishery, because only minor 

 quantities of yellowtail were taken on Georges 

 Bank by the extensive otter-trawl fisheries prior 

 to 1947. 

 These recaptures do indicate only a small 



amount of intermingling among the populations 

 on the major fishing grounds. The Nantucket 

 Shoals, which are shallower than the preferred 

 depth of the yellowtail flounder, apparently limit 

 migration across them. Considering only the 

 tagged yellowtail released in adjacent areas, we 

 noted that none of the 54 fish recaptured from the 

 514 released in subarea O were found across 

 Nantucket Shoals, and only 1 of the 15 recaptures 

 from the 408 fish tagged off the east side of Cape 

 Cod was found south across the Shoals. South 

 Channel appears to be somewhat less of a deter- 

 rent to movement because 1 fish tagged in subarea 

 O west of the Channel was found east of it and 

 3 of 12 recaptures from the 51 tagged in subarea 

 N just east of the Channel were found west of it. 

 In general, then, the yellowtail are to be found 

 in relatively localized populations, which may 

 make short, seasonal migrations. Our most dis- 



