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tion to cold waters, north to south—a so-called genetic cline—evolving either differing levels of antifreeze in
the blood or different migratory patterns. What these populations have in common is a preference for relatively
warm water on the banks (2° to 4°C, or 36° to 39°F) for spawning. By contrast, most cod stocks in the eastern
North Atlantic spawn in inshore waters, which are bathed with the warm waters of the North Atlantic Current
(as the Gulf Stream is called after it passes the Grand Banks). The temperature of the Labrador Current only
partially accounts for the cod's preference for the banks on this side of the Atlantic. The spawning sites also
evolved due to the direction and force of the currents, which act like a conveyor belt, delivering the juveniles
to the proper place in the ecosystem, at the right time, for their development.
The dramatic coastline of Newfoundland has earned it the affectionate sobriquet, “The Rock.”
Smaller coastal populations, however, have developed in the northeast coast bays of Newfoundland—Notre
Dame, Trinity, and Bonavista—as well as Placentia Bay in the south. Fish overwinter in these sheltered bays,
spawn in the spring, and wait for the spawning populations of capelin to come to them in the summer. Fish on
the Grand Banks follow a current gyre, feeding on the offshore populations of capelin and sand lance as they
go and in winter only have to swim a short distance to the edge of the banks to escape the cold waters of the
Labrador Current. Other great stocks, from the northern banks and Bonavista Corridor, converge on the north-
east coast in pursuit of capelin.
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