The Natural History of Whales

There are 86 species of cetaceans (whales, dolphins and porpoises).  Their size varies from about 2 1/2 feet to 108 feet (the biggest animal that has ever lived is the Blue whale). Different species live in all the oceans of the world and even in some rivers.  Some feed on the smallest of creatures and some feed on giant squid 2 miles beneath the surface of the ocean.  Some just swim along with their mouths open to feed and others use echolocation (biosonar) in the pitch black, high pressure, cold, deep ocean depths. Some sing and their voice can be heard across an ocean.  How do they accomplish all these marvelous feats? Take a walk with Dr. Jerald Bernstein among the cetaceans and find out!