In the winter an ice shield surrounds each cage and underwater noise makers are active to keep seals away. With any farming situation, the sites must be kept clean and the fish little stressed to prevent disease and its rapid spread. The cage sites are granted by the New Brunswick Department of Fisheries and Aquaculture and they also specify the maximum number of fish per farm. For a discussion, the latest information and lots of links on salmon aquaculture refer to Fundy Net Aquaculture files. Spawning in warm waters, the adult tuna migrate north to feed on schooling fish such as herring.
Bluefins maintain a constant warm body by continuously swimming.
Up to the 1960's bluefin tuna were regularly caught in the Bay of Fundy but apparently, responding to a drastic decline in herring in the 1970's, tuna were scarcely seen until the late 1980's. A prized sport fish because of its size, predictability and power, a sport fishery in the Bay does not exist. There are also no licenses in the Grand Manan archipelago but fishers from Nova Scotia cruise the Bay during the summer and early fall looking for bluefin tuna. Because the fish are so valuable to the Japanese sushi and sashimi market, some fishers use planes to spot tuna. The tuna are caught with a hand thrown harpoon equipped with an electric charge to stun the fish.