Gray Whale Migration
Fall: October, November, December

Gray Whale Migration Route
(Click on map for more)

Heading South
It's prime time again for one of the greatest shows in the marine world: the California gray whale's migration from frigid arctic feeding grounds to Mexico's balmy birthing lagoons. Each October or November, gray whales begin plowing south by the hundreds from their summer feeding grounds between Alaska and Siberia. These 40-ton giants complete a 5,000 to 6,000-mile journey south to their winter mating and birthing grounds in an average of 55 days by swimming nonstop. In December they begin arriving in the four calving and mating lagoons of Mexico's Baja California coast. (Click on the map dots to read more about each lagoon.) They gather by the thousands in these sheltered bays and lagoons to court and mate. Many females give birth to calves conceived in these lagoons the winter before, after a gestation period of 13 months. (Around the age of five years, mature female gray whales usually start having a calf every two years of their long lives.)


Clip: Whale Up Close!
Watch It Now


California gray whales travel farther than any other migratory mammal on Earth. Following a path that's usually within a few miles of shore, they swim just below the water surface. During the fall and again in spring, people who enjoy whales make their own journeys to the Pacific Coast; they hope for a look at these gentle giants passing by. Thanks to their nearshore migratory path, gray whales are seen by more people, in more places, than any other type of whale. Get your own up-close look with this video clip!

Lessons for Fall

  • Why Head South? Does it surprise you that the whales would go all the way from Alaska to Mexico when they aren't going to give birth? Why do they go if they're too young to mate? See what two experts think.
  • The Migration Trail: Any Shut-eye Along the Way?
    Do whales rest along the way? How? For many years, scientists were unsure about this question. Read what naturalist Tom Lewis says about a whale's rest or sleep.
  • Southbound Babies: Two Scientists Speak
    A few babies each year are born during their mother's migration south—before reaching the warm, sheltered nursery lagoons. What does this mean for the babies?
  • Hitchhikers: Free Rides on Gray Whales
    Imagine carrying a ton of hitchhikers on your back! Gray whales do this all their lives. Grays are more heavily infested with a greater variety of parasites and hitchhikers than any other cetacean. Who's riding, and why?
  • Adaptations That Help Gray Whales Survive
    Dissecting a dead whale, a marine biologist could see that it spends its life in the ocean, lives at least part time in very cold water, and migrates long distances. How? By understanding how whale bodies and behaviors are adapted to habitat and food requirements. This lesson looks at a gray whale’s body from head to tail to see just how this marine mammal is perfectly designed for the life it leads.
  • Who Is That Whale? Gray Whale Photo ID Matching
    How are those barnacle clusters carried by gray whales of enormous use to scientists? With circles and arrows on whale photos, Dr. William Megill teaches you how barnacle clusters identify individual whales. Test your abilities with Dr. Megill's photo quiz!
  • Sink or Float? Investigating Buoyancy
    What makes it possible for animals as heavy as gray whales to easily float and move in water? These investigations into density and the properties of salt water can help shed light on that question.