BIOLOGY AND NATURAL HISTORY 277 



when other fishing is scarce, and is present in quantity particularly in the 

 Beaufort section. 



As with other fishes, commercial catches are often possible when angling 

 is not. In this case, the reason is the cold: spotted trout often become numbed 

 by cold and can be easily caught in nets, whereas they would not take bait. 



BLUEFIN TUNA , 



Thunnus thynnus (Linnaeus) 



This fish occurs all over the world, in the Atlantic and Pacific oceans 

 and the Mediterranean and Black seas. On our Atlantic coast, its presence 

 has been substantiated from various points between the northern Bahama 

 Islands and Newfoundland but this does not mean that it necessarily occurs 

 without gap along that entire coast. Concentration points are the Bimini- 

 Cat Cay section of the Bahama Islands; New Jersey; Long Island; the 

 Gulf of Maine; the Wedgeport-Liverpool section of Nova Scotia. It is 

 uncommon off Florida and Bermuda and is reported as formerly common 

 off Ocean City, Maryland, but not present there in recent years. There are 

 two records of bluefins near Beaufort; one in 1885 and one in the early 

 1900's. 



The prevailing impression is that the bluefins appear from somewhere 

 south of Bimini, passing that island in great numbers and very swiftly, in 

 May and June, and on a northbound migration which finally lands them 

 in Nova Scotia or the southern part of Newfoundland. The fish are off 

 New Jersey in August and September; in the Gulf of Maine from June to 

 September, with the height of the run in July. The rod and reel record of 

 927 pounds was taken on August 25, 1940 in Ipswich Bay, Massachusetts. 

 The average size of the fish varies with locality from 60 pounds to over 

 200. 



The bluefin is known to be very dependent on temperature and salinity 

 conditions; the run in some localities extends for some time and in others 

 only a very short time ; in some the presence of the fish is irregular and in 

 others regular enough to warrant a profitable commercial fishery in station- 

 ary nets, as off Sicily, Sardinia, and Tunis. There are constant rumors of 

 its presence off North Carolina, probably based on the assumption that it is 

 migratory and must pass there. It is possible that there is no run of bluefin 

 there at all, but that this is a case of circumscribed population units. It is 

 also possible that the fish do pass there but too far out or too deep — or both 

 — to be noted by fishermen or anglers. , 



The breeding habits of this fish have been studied on various European 

 grounds and work on sex and growth rates has been done off Long Island. 



The fish referred to in North Carolina as "school tuna" does not mean, 

 as it does elsewhere, bluefin tuna under 60 pounds. It refers to a different 



