The ocean’s biggest animal is the blue whale on Earth, for that matter, is a blue whale. Blue whales can be as long as 100 feet and weigh up to 200 tons! They eat mainly krill and plankton, but will also consume small fish if they are available. A blue whale can filter one million gallons of water per day while feeding, which sounds like a lot until you compare it to how much oil spills into oceans every year from ships or platforms around the world. In fact, scientists estimate that between 10-30% of all marine life dies from oil pollution each year.
Blue whales are baleen whales, meaning they have bristles made of keratin (like our hair) which act as a filter when they feed. A blue whale has roughly 320 pairs of these bristles hanging from each side of its mouth, the longest ones can be more than 8 feet long! They use their extremely long tongues to help push fish and other prey into their mouths. Once there, the bristles block anything larger than two inches long, so they don’t end up swallowing too much water and choking to death.
Because of their large size, blue whales can travel very quickly through the water at around 20 mph (32 km/h). If that’s not fast enough for them, they can also produce a burst of speed reaching up to 35 mph (56 km/h) for a short time. They do this by contracting their muscles and moving the tail upwards, creating an area of low pressure that sucks water in. This is known as “updraft feeding.”
Blue whales can be found all over the world, usually in cool, temperate waters such as the Antarctic and Pacific oceans.