Blue whales are baleen whales, which means they have fringed plates attached to their upper jaws. These animals feed by gulping huge mouthfuls of water. The tongue forces the water out of the whales mouth and thousands of krill are left behind. A single Blue whale consumes about four tons of krill a day.
Range and Threats
Blue whales live in small groups or pairs in all the world's oceans. Often times they spend the summer months in polar waters and spend winter months closer to the equator. The only threat for Blue whales are from sharks, killer whales, or injuries fro large ships. Unfortunately, the Blue whales are classified as endangered due to these threats.
Blue whales can grow up to 100 feet and weigh as much as 200 tons. These whales are blue-gray with light gray spots around the whole body. Their dorsal fins are extremely small and has long, thin flippers. The tail on a whale are positioned horizontally rather than vertically like most fish. The tail is called a fluke. Each fluke on a whale is slightly different depending on what type of whale it is.
Female blue whales give birth to calves every two to three years. they are pregnant for one year before giving birth. When born, a blue whale calf is about 23 feet long and weighs 5,000 to 6,000 pounds. A nursing blue whale produces over 50 gallons of milk a day. The milk allows the calf to gain weight at a rate of 10 pounds an hour or over 250 pounds a day. The blue whale finally reaches sexual maturity at about 10 years old.
Whales use echolocation to communicate. Whales use sound to navigate, to detect food, and to communicate with one another. The sounds they make sounded like low grunts, humming, moans and clicks. The deep vibrations made by Blue Whales can travel thousands of miles.