40' 



30 c 



20' 



10° 





1000 Folhoms 





INSIDE 



OUTSIDE 



JUN 



3 



\ 



JUL 



4 



1 



AUG 



2\ 





SEP 



12 



6 



OCT 



l 



1 1 



100° 90° 80° 70° 60° 50° 40° 



Figure 1. — Location of recaptures of white marlin tagged in the western North Atlantic 

 Ocean north of lat. 33°N between Cape Hatteras, N.C.. and Cape Cod, Mass.. in summer. 

 The frequency of recaptures by months in each area is shown. The number of recaptures at 

 each site is indicated by the size of the dot and. if more than 1. by the adjacent number. 



available to fishing there during as many as six sea- 

 sons. This was shown by a recapture in June 1972 of 

 a fish which had been released in August 1967. 

 These results suggest that most of the white marlin 

 which occur in summer in this area are of a single 

 (but not necessarily genetically distinct) stock. We 

 will tentatively name this the '"middle Atlantic" 

 stock, after its summer habitat off the middle Atlan- 

 tic coast of the United States. 



Fifteen of the new returns from outside the 1 .000 

 fathom contour in Area A, which were recaptured 

 in September and October, and the two earlier ones 

 which were recaptured in the same period, give 

 considerable information on how the white marlin 

 leave the inshore fishing grounds between Cape 

 Hatteras and Cape Cod in late summer and early 

 fall (Fig. 3). The other two offshore recaptures, in 

 June and July, give indications of how white marlin 

 approach the shallower waters in spring and early 

 summer. The lack of any offshore returns from 

 Area A in August, when inshore returns are at a 

 maximum, indicates a strong tendency for white 

 marlin to concentrate on the continental shelf in 

 that month. 



42° 



40° 



• RELEASE 

 O RECAPTURE 



--' S> 



,' CAPE' HATTERAS 



-l,' CAP 



76° 



72° 



70° 



Figure 2. — Local movements of tagged white marlin in- 

 side the 1,000 fathom contour between Cape Hatteras 

 and Georges Bank. Releases were in July (4) and August 

 (2): returns were in August (5) and September (1). Recap- 

 tures in years subsequent to year of release are not 

 shown. 



214 



