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A fin whale swims off the coast of Los Angeles. These whales can get up to 70-feet long and weigh up to 150,000-lb, making it the second largest animal on earth.

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A sea lion raises a flipper off the coast of Los Angeles.

Mae Ryan

A Marine Biologist shows krill, left, small crustaceans that whales eat with their baleen, right, plates that filter food from the water.

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A family listens to marine biologists explain the rarity of the fin whales, which are the second largest mammal on the planet.

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A crew member from the The Aquarium of the Pacific gets ready to take off on a Harbor Breeze Cruise for whale watching.

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A megapod of common dolphins swim off the shores of Catalina Island.

Whale watchers off the Southern California coast saw a lot more than they expected when a chartered boat descended on a large pod of 23 gray whales, which usually travel alone or in groups of two or three as they migrate. 

Gray whale season started on Dec. 26, 2012, and lasts through April.