Mid to late March is the peak of the Gray Whale migration in the Bay Area as an estimated 15,000 whales head north to their summer feeding grounds in the Arctic. December and January are good months as well, when they migrate south. Gray Whales stay close to shore so you can often observe them from the coast. This annual Gray Whale migration is perhaps the longest migration of any mammal, encompassing a roundtrip of 10-12,000 miles that takes between 4 and 6 months!
After feeding all summer in the nutrient rich waters north of Alaska, the whales head south to their winter breeding and calving grounds in the lagoons of Baja California. The mothers and calves are generally last to leave Baja, so expect to see moms and babies later, toward April and sometimes May.
Gray Whales are one of the few mammals where the females are larger than the males, weighing up to 40 tons. Newborns weigh between 1,100 and 1,500 pounds and are about 15 feet long, quite a large animal considering the gestation period is only 12-13 months. Gray whales are also known for their white patches interspersed on their gray bodies, where barnacles and whale lice attach themselves and live. It is believed that an average whale carries as much as 400 pounds of barnacles and lice on its body.
We're lucky to see Gray Whales at all. Hunted extensively in the late 1800s through the early 1900s, they nearly became extinct. It was estimated that as few as 2,000 Gray Whales remained when protection was finally established in 1946 through an international agreement. Today, the population is an estimated robust 17,000 to 20,000, and they were removed from the endangered species list in 1994.
Learn more about Gray Whales at the Crab Cover Visitor Center. You can also join Naturalists Nancy or Michael for the upcoming annual whale watching expeditions. Every trip is different, with chances of seeing Gray Whales along with Harbor Seals, Sea lions, Sea Otters, and a variety of birds. Our trips are aboard the 'New Captain Pete', leaving out of Half Moon Bay.