Table 31 Releases and returns for giant (over 120 kg) blucfin tuna tagged in 

 Newfoundland waters, by year of release, months at large, and area* of recaptuic 



which feed in New England and Ca- 

 nadian waters in summer and early 

 fall and those which spawn in the 

 Gulf of Mexico in spring (Section 

 VD3) As noted previously in this 

 section, an "indirect" northward mi- 

 gration from the Straits of Flonda to 

 Massachusetts coastal waters has also 

 been recorded. 



Another important tag return, 

 which was not from the above re- 

 lease groups, connects the feeding 

 area olf New England and Canada 

 with the spawning area for giants in 

 the Gulf of Mexico. This fish, which 

 was tagged when it was in the small 

 size group, was released August 4, 

 1 966, 38 nautical miles (70 km) south 

 by west of Martha's Vineyard, Mas- 

 sachusetts, and was recaptured April 

 18, 1976, in the north central Gulf of 

 Mexico, 135 nautical miles (250 km) 

 south by east of the Mississippi River 

 entrance (Figure 79). Its length when 

 released was about 56 cm and af\er 

 nearly 10 years at liberty, the longest 

 such period of which we have knowl- 

 edge for a tagged Atlantic bluefin 

 tuna, it was reported as 2 1 8 cm. Thus 

 the fish was age 1 + when tagged, and 



age 1 1 , or slightly less when recap- 

 tured Although this fish was in the 

 small size group when tagged, it must 

 have been a giant when it made its 



last southward migration. Since less 

 than 1 percent of the returns from 

 bluefin tagged in New England wa- 

 ters have been from outside the west- 

 em North Atlantic, it is highly prob- 

 able that this fmal migration was from 

 the New England or Canadian feed- 

 ing grounds The main significance 

 of this return is the establishment of 

 a connection between the nursery area 

 south of Cape Cod and the spawning 

 grounds in the south Moreover, it 

 most probably also represents the sea- 

 sonal migration of large bluefin from 

 the northwestern Atlantic feeding 

 area to their spawning areas 



This IS the third important link 

 between the spawning area in the Gulf 

 of Mexico and the summer feeding 

 grounds off the noitheastem United 

 States As noted previously m this 

 section, a large bluefin made a "di- 

 rect" migration from waters north of 

 Cape Cod into the Gulf of Mexico, 

 where it was recaptured during the 

 spawning season. Another fish made 

 an "indirect" migration, which might 

 well have originated in the Gulf of 

 Mexico, from the Straits of Florida, 

 where po.st-spawning bluefin are 

 prevalent, to New England waters. 



Thus tag returns have produced 

 considerable information on move- 

 ments of large bluefin within the 

 western North Atlantic, and from it 



50' 



Yin '72- -xn' 73 



40* - 



30- - 



LEGEND 



RELEASE LOCALITY 

 RECAPTURE LOCALITY 



- LESS THAN '0 MONTHS AT LIBERTY 



— MORE THAN^OMONTMS AT LIBERTY 

 RELEASE DATE RECAPTURE DATE 



II'64 • 



*<7rf LiNis joiNine DCLCAses AMOneruPfis 



ARC DIACKiyU'TIC AMD ARC MOT INTEMOCD 

 TO RCRRCSCMT kneiATIOM ROOTCS 



80* 



SO' 



50* 



40* 



Figure 77. Geographic disU-ibution of bluefin tag relea.se and recapture data from 

 Newfoundland tagging studies 



118 



