Atlantic puffins spend most of the non-breeding months at sea. After their May–August breeding season ends, they migrate far offshore and forage over wide areas in the open ocean rather than staying near their colony. Many populations spend the winter months hundreds of miles offshore in the North Atlantic, ranging from the western Gulf of St. Lawrence northward and then south and east across deep, productive waters off the U.S. Atlantic coast, the Canadian shelf, and beyond, before returning to their breeding sites in spring. The exact routes and wintering hotspots can vary by colony and year, but the general pattern is: depart the colony after breeding, travel to offshore, nutrient-rich waters, spend the winter feeding at sea, and return to the colony to breed again when conditions become favorable. This behavior has been revealed by tracking studies that tagged puffins and followed their movements during the colder months.