The gray whale is both a conservation failure and success story. The gray whales that inhabited the Atlantic Ocean were hunted to extinction in the 17 th century. Today, another gray whale population found in the waters off Korea and Japan remains near extinction. But the population that migrates along the California coast between the Arctic and Baja Mexico has increased to more than 20,000. These are more than 20,000 of Earth's champion migrant mammals.
Gray whales spend the summer feeding in the rich waters of the Bering Sea, near Alaska.
In the fall, they depart for a 5,000-mile voyage to the warm waters of Baja Mexico. Here the pregnant cows give birth. They begin the return trip to Alaska about February. The 10,000-mile round trip is the longest known migration of any marine mammal. Whether headed north or south, gray whales present a rare spectacled for land-bound humans.