the United States and Cuba it was 

 impossible to verify this migration 

 route completely by fishmg in the 

 Old Bahama Channel itself. 



The third and most direct pos- 

 sible route from the Windward Pas- 

 sage to the northern feeding grounds 

 is through the Crooked Island Pas- 

 sage (Figure 31). Bluefm tuna are 

 abundant east and north of the Baha- 

 mas in spring (Shingu et al. 1975) 

 and some of them probably spawn in 

 these waters (Table 25, Figure 70). 

 It also appears that these fish move 

 northward m May and June (Shmgu 

 et al. 1975), as do those in the Straits 

 of Florida Several exploratory 

 longline sets were made in the 

 Crooked Island Passage and west of 

 Great Inagua island from research 

 vessels of the Woods Hole Oceano- 

 graphic Institution in May and June 

 of 1958 and 1961 (Mather 1959, 

 Anonymous 1969). No bluefin tuna 

 were caught on any of these sets, nor 

 did we note any of the gear damage 

 which these fish often cause when 

 they have been hooked and subse- 

 quently escaped. This, of course, did 

 not prove that no bluefin follow this 

 route, but, in our opinion, the fishing 

 results and other data indicate that 

 they follow the other two routes in 

 much greater numbers 



After the giant bluefin have 

 spawned in these southern areas, they 

 migrate northward to feeding grounds 

 off northeastern North Amenca and, 

 in some years, large contingents of 

 them go on to feeding areas off Nor- 

 way. 



The evidence for these migra- 

 tions has been discussed in preced- 

 ing paragraphs Daily records of 

 catches at Cat Cay for numerous pre- 

 and post-World War 11 years (per- 

 sonal communications) show that the 

 passage through the Straits of Florida 

 occurs in strength, as indicated by 

 availability to surface fishing from 

 early May to about June 20. 



As noted previously, longline 

 catch records (Anonymous 1962, 

 LeGall 1974, Shingu et al 1975) in- 

 dicate that a parallel but much more 

 dispersed migration takes place in 

 about the same period along the oce- 

 anic edges of the Bahamas, and for 

 considerable distances east and north 

 of them. After passing north of these 



islands, this migration merges, at least 

 partially, with the one moving north- 

 ward from the Straits of Florida The 

 migration through Atlantic waters 

 east of the Bahamas has not been 

 observed visually, to our knowledge, 

 and sightmgs of large bluefin between 

 the Bahamas and Cape Hatteras have 

 been extremely rare In fact, the oc- 

 currence of surface schools of giant 

 bluefm fravellmg steadily in one di- 

 rection off the northwestern Baha- 

 mas IS a stnctly local phenomenon 

 which is unique in the western Atlan- 

 tic. It is quite similar to the periodic 

 runs of bluefin on which the traps at 

 many localities in the Ibero-Moroc- 

 can Bay and the Mediterranean de- 

 pended, particularly the "return" run 

 of spent fish in July and August. 



In addition to the lack of sight 

 records, no tag returns revealing the 

 movements of giant tuna between the 

 Bahamas and Cape Hatteras have 

 been obtained to date Exploratory 

 longline fishing results (Anonymous 

 1962, Zharov 1965) indicate that 

 these fish are much more available in 

 waters east of the Gulf Stream than 

 in those west of it, just as they are in 

 the northern Straits of Flonda Be- 

 cause of the tendency of bluefin tuna 

 and other large pelagic fishes to travel 

 in favonng currents when migrating 

 for great distances (Sara 1973), we 

 assume, in the absence of more pre- 

 cise data, that many large bluefin 

 swim in the Gulf Stream northward 

 to the vicinity of Cape 1 latteras Af- 

 ter the Stream has passed the Cape 

 and turned eastward, aggregations of 

 fish leave it successively, according 

 to our hypothesis We speculate flir- 

 ther that the distance that a given 

 group has travelled in the east-flow- 

 ing current may be an important fac- 

 tor in determining where it enters the 

 coastal waters. The first fish to leave 

 the Stream after it passes Cape 

 Hatteras may approach the coast any- 

 where from off the Chesapeake Bay 

 entrance to Cape Cod This is indi- 

 cated by a tag recovery off the Chesa- 

 peake Capes (Figure 76), catches in 

 traps off northern (peninsular) Vir- 

 ginia, New Jersey, and Long Island, 

 and occasional sightings by fisher- 

 men off southern New England of 

 giants U^avelling eastward, singly or 

 in small schools, in late June and 



early July (personal communica- 

 tions). We believe that the majority 

 of these fish eventually enter the Gulf 

 of Mame. Larger contingents prob- 

 ably follow the easterly current far- 

 ther and tend to enter the Gulf of 

 Maine more directly, presumably 

 through the Great South Channel in 

 many instances. Giant tuna usually 

 amve off northern Massachusetts in 

 June, and off southern Maine and 

 southwestern Nova Scotia in July. 

 They often arrive in the Halifax area, 

 however, in June. The latter may have 

 left the Gulf Stream at about the same 

 time as those which entered the Gulf 

 of Maine, but followed a more direct 

 course to this area. Large aggrega- 

 tions which have remained in the east- 

 erly current even longer may eventu- 

 ally enter the Gulf of St. Lawrence 

 and Newfoundland waters in the lat- 

 ter half of July The times of arrival 

 in American waters are from Section 

 IVC2. In some years, considerable 

 numbers of bluefin persist in fol- 

 lowing the Stream much farther and 

 eventually reach Norwegian waters 

 in August, September or October 

 (Figure 75) 



These transatlantic migrations 

 are discussed in the following Sec- 

 tion C3 The local movements within 

 the feeding area between Cape Cod 

 and Newfoundland have been de- 

 scribed previously in our discussion 

 of tagging results. 



The southward migration of large 

 bluefin in late fall from their warm 

 season feeding areas to their south- 

 ern wintering areas (Figure 14) 

 around the Greater Antilles and off 

 Brazil is one whose details are un- 

 known Most of the large bluefin 

 leave their coastal feeding areas be- 

 tween late September and early No- 

 vember (Section IVC2) As previ- 

 ously stated, tag returns (Figure 79) 

 show a "direct" migration by a giant 

 fish from the southwestern Gulf of 

 Maine in July 1974 to the western 

 Gulf of Mexico m May 1975 and a 

 long term "indirect" migration from 

 the nursery area for young bluefin 

 off southern New England in August 

 1 966 to the north central Gulf of 

 Mexico in April 1976 These two 

 returns show movements from the 

 feeding area to the spawning grounds, 

 but do not tell us where the fish spent 



121 



