The Blue Whale is the largest animal on Earth, growing up to 100 feet long and weighing up to 200 tons. They are found in all of the world's oceans and are known for their distinctive blue-gray color and mottled appearance. Blue Whales are filter feeders, consuming up to 4 tons of krill per day. They are also known for their unique vocalizations, which can be heard for miles underwater. Unfortunately, Blue Whales were hunted to near extinction in the 20th century, but conservation efforts have helped their populations recover. Today, they are still considered an endangered species and face threats from climate change, pollution, and ship strikes.