Mexico’s Sea of Cortez is home to one-third of the world’s whale and dolphin species. Twelve species of annual whales live in these waters, including the blue whale (the largest animal in the world), humpback whales and gray whales. Gray whales are relatively large - about twice the length of an Orca (killer whale) and half the length of the enormous blue whale. Most adult gray whales are about ten to thirteen meters (35 to 45 feet) long, and weigh twenty-two to thirty-eight tonnes (20 to 35 tons), with females tending to be larger than the males. Named for their medium gray color beneath the water, which is marbled with lighter patches, gray whales appear to be a whitish-blue color at the water’s surface. Each whale has a unique skin pigmentation color which allows individuals to be identified, and these patterns often include round white markings that result from barnacles that have fallen off.

Undergoing one of the longest animal migrations in the world, gray whales inhabit the chilly waters of the Bering Sea (off the coast of Alaska) in the summer, and migrate to their annual birthing grounds in winter - the warm lagoons on the coast of Baja California Sur, Mexico, some 6,000 kilometers (4,000 miles) to the south. Exactly why the gray whale and many other whale species travel to warmer climes to breed and give birth is unknown. Yet, each year, gray whales depart from the Bering Sea in October, and by December, they are usually between Monterey and San Diego, where thousands of residents watch up to 200 whales a day stream past their shores. They reach the central coast of Baja by late December, where half of the females mate and the other half give birth. Each year, a few stragglers can be seen arriving as late as February. These slowpokes encounter northbound whales returning from Baja and often hit the brakes, turn around and join them. (more…)