The blue whale (balaenoptera musculus) is the largest animal to ever live. Today, it is an endangered species due to humanity's hunt for them. They live in all the world's oceans and have a diet based on other marine life. Due to their commercial use, the blue whale is on the edge of extinction and is fighting to survive. The United States government and other organizations have stepped in to save this creature but there is still work to be done. There has been efforts to monitor and study these immense creatures and valuable information has been collected to comprehend the blue whale. It is ironic how the biggest creature known to man is about to disappear because of us. Even though the blue whale is endangered, mainly because of its economic use, it is a magnificent mammal, valuable to the diversity and life of the ocean that should be preserved. Blue whales appear blue colored underwater but on the surface they are gray-looking (National Geographic [NG] 1). They form part of the Balaenopteridae family "whose subspecies contain the largest animals ever known to have lived on Earth" (Perry, DeMaster, Silber 38). Blue whales are baleen whales because they have fringed plates composed of baleen, a fingernail-like material which is attached to their upper jaws (NG 1). It is believed that they use low frequency calls with high intensity to communicate and can be detected from a distance of 200 kilometers on bottom-moored hydrophones (Dunn & Hernandez 1084). The blue whale is one of the loudest animals on the planet. They swim at about five miles per hour but when being persecuted they reach a speed of approximately 20 miles per hour. Their lifespan is around 80 to 90 years, the oldest blue whale to be recorded was 110 years old, this creature is one of the most long-lived animals on the planet (NG 1). The main prey of blue whales is a "tiny shrimp like animal" (NG 1), named Krill, which is mainly found on cold areas with upwelling currents (Perry, DeMaster, Silber 42). On the Pacific coast of Baja, "blue whales have been reported to feed on concentrations of the pelagic red crab (Perry, DeMaster, Silber 42). Both male and female reach sexual development at 5-15 years (Perry, DeMaster, Silber 42). It takes about a year for a baby blue whale to born and when it does, it weighs about 3 tons and measures a length of about 8 meters. It consumes only the milk the mother provides and acquires 200 pounds every day for its first year (NG 1). The blue whale is found in all the world's oceans, the