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Gray Whale Migration & Whale Watching. Physical Characteristics. Adult females are slightly larger than males and measure ~50 feet long. Both sexes weigh 30-40 tons. A 45-foot, 35-ton gray whale is about the same size as 10 large elephants. Adult males measure 45-46 feet in length.
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Physical Characteristics • Adult females are slightly larger than males and measure ~50 feet long. • Both sexes weigh 30-40 tons. • A 45-foot, 35-ton gray whale is about the same size as 10 large elephants. • Adult males measure 45-46 feet in length. • The largest gray whales have flukes, or tails, that may span 10 feet. • Gray whales are gray with white patches.
Gray Whale Facts • The white patches mainly consist of barnacles and whale lice, which are attached to their skin. • On average, a whale carries over 400 pounds of barnacles on its body. • Whales rely on a layer of blubber up to 12 inches thick to help them maintain their body temperature. • Whales are voluntary breathers, which means they have to remember to breathe. This makes sleeping difficult. • Gray whales live to be 50-60 years old. http://www.biosbcc.net/ocean/marinesci/05nekton/GWsouth.htm http://www.biosbcc.net/ocean/marinesci/05nekton/GWsouth.htm
Gray Whales’ Food Source • Except for babies, gray whales eat little or nothing during migration and in the lagoons of Mexico. • When they get home to their arctic feeding grounds, which are ice-free during the summer, they feast for 130-140 days before heading south again. • It takes over 600 pounds of tiny krill (amphipods) and mysis shrimp to fill a gray’s stomach. • Gray whales have 2-4 throat grooves about 5 feet in length. • These grooves expand during feeding, which requires a large intake of water and mud. • Gray whales feed on the bottom of the ocean floor, sifting through the mud with their baleen. http://www.pbs.org/kqed/oceanadventures/educators/library http://www.pbs.org/kqed/oceanadventures/educators/library
What is a Baleen Whale? • Gray whales don’t have teeth; they have baleen. • Baleen is made of plates of keratin, a fingernail-like material that frays out into fine hairs. • Baleen hangs on either side of the jaw, where teeth might otherwise be located. • The plates are off-white and are 2-10 inches in length. • The whales feed on the right side of their mouths, and sediment is strained by the baleen to catch crustaceans. • The crustaceans are trapped in the baleen, which the whale licks with its tongue to dislodge and eat them. http://www.sfgate.com/getoutside/photos/dec97/baleen.gif http://www.biosbcc.net/ocean/marinesci/05nekton/GWmigration.htm
Gray Whale Habitat • They are found only in the Pacific Ocean. • Along the coastline, they have a population of ~26,000. Around Korea and Japan, a small group of 100-250 whales is on the brink of extinction. • Gray whales became extinct in the North Atlantic Ocean in the 17th century due to hunting. • The whales’ habitat ranges from the Arctic Ocean northwest of Alaska to the Baja peninsula in Mexico. http://www.biosbcc.net/ocean/marinesci/05nekton/GWmigration.htm
Gray Whale Behaviors • The whales migrate to give birth and mate in a warm climate. • They migrate along the coastline and are the only whale that eats from the ocean floor. • Gray whales form small pods from 3-16 members. • Spy-hopping is a gray whale behavior where the whale pokes its head up to 10 feet out of the water to look around. • Gray whales also breach, or jump partially out of the water, causing a loud noise when they land. • This may be a form of communication, as are their various grunts, clicks, and whistles. http://www.pbs.org/kqed/oceanadventures/educators/library http://www.pbs.org/kqed/oceanadventures/educators/library
Baby Whale • The baby whale weighs 1,100-1,500 lbs. and is ~15 feet long at birth. • The warmer waters of Baja Mexico’s shallow lagoons help newborns conserve body heat. • They are born lean and without blubber. • The calves nurse for about 6 months, during which time the mother provides up to 50 gallons of milk each day. • The milk contains 53% fat, and calves may gain 60-70 pounds daily, building up blubber for their cold trip north. • Female whales help each other at birth. The “Auntie” pushes the newborn calf up to the surface to ensure it does not drown.
Whale Nurseries • Gray whales migrate farther than any mammal on Earth. • Each year they swim from the cold Arctic to warm Mexican lagoons and back again, traveling over 10,000 miles. • They leave the cold waters of the Bering Sea in November and swim for 55 days nonstop. • In January they arrive in the warm, safe lagoonsof Mexico’s Baja Peninsula, just in time to give birth. • The whales remain in the lagoons for 3 months and start their return trip to the Bering Sea in March. http://www.pbs.org/kqed/oceanadventures/educators/library/