Blue whales, monarchs of the Pacific coastline
Largest creatures to have lived on Earth now number only 10,000.
Sat, May 22, 2010 at 06:20 AM
Photo: ZUMA Press
The West is home to many migratory animals, the most remarkable of which is the majestic blue whale, the largest animal ever to have lived on Earth. It graces the Pacific Northwest coastline during its summer migration to the most productive ecosystem on our planet: the polar seas.
People have much in common with whales: We both like to eat, mate, touch, talk, sing, sleep, travel and listen.
Prior to commercial whaling, the number of blue whales was estimated at 200,000. Today only about 10,000 of these awesome creatures remain.
The enormity of a blue whale is breathtaking. They are about five times larger than the largest dinosaur. The only other organisms comparable in size are the few remaining champion trees. About 6 1/2 blue whales would fit — end to end — inside the largest known tree in British Columbia, the Cheetwhat Lake western redcedar.
Blue whales are 98 feet long with a mass of about 146 tons. Their hearts weigh 992 pounds (the size of a Volkswagen Beetle) and pump 14,109 pounds of blood. Their horizontal tail has the power of a 500 horsepower outboard motor. They can travel at 31 mph for two hours at a time and 43 mph for 10-minute intervals.
When a blue whale takes a breath it is equivalent to eight for a human. As they surface, they fill 80 to 90 percent of their lungs with air. Humans fill only about 20 percent. At rest, their heart rate is nine beats per minute. They can remain submerged for up to two hours and dive to depths greater than 379 feet (equal to the tallest tree on Earth — a coastal redwood named Hyperion).
Although single-celled algae stick to the whales’ underbellies, making them appear yellow to silver, their real skin color is dark. That's because whales use oxygen very efficiently due to special muscular protein (myoglobin), which also prevents them from getting nitrogen in their blood, preventing an affliction known to divers as the bends.
There are two distinctly different populations of blue whales: one in the northern and one in the southern hemispheres. They do not intermingle. They both spend the summers feasting in the polar seas where long days promote growth of billions of tonnes of plankton (minute plants and animals). They spend their winters mating and calving in warm equatorial waters.
Blue whales don't have teeth. Instead they have an exquisite filtration system called a baleen. Three hundred and sixty plates hang from the upper jaw. One gulp contains about 5 1/2 tons of water. As the mouth closes, water is expelled through the baleen plates and filled with plankton, crustaceans and small fish (particularly krill). On average a blue whale will eat between 1,984 and 9,039 pounds of plankton for about 120 consecutive days.
Whales use sonar for radar and as a communication system. They are the loudest animal on earth at 188 decibels (louder than a 747 jet engine). We have yet, and may never, understand their complex language.
Blue whales are the monarch of the seas, invincible yet gentle. To be in the wild and in the presence of a whale is the most humbling of experiences. They teach us a message, a message of respect for one another, and a respect for all nature.
Dr. Reese Halter is a conservation biologist at Cal Lutheran University, public speaker and founder of the international conservation institute Global Forest Science. Follow him @ twitter.com/DrReeseHalter.
Also on MNN: Read Halter's explanation of why we have more in common with wolves than we realize
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