Blue whales produce reverberating, low-frequency moans that can be heard in deep ocean waters up to 100 miles away. These moans enable the whales to remain in contact across a vast expanse of ocean.
Despite their enormous size, the Blue Whale's diet consists almost entirely of krill, tiny shrimplike crustaceans occurring in all oceans of the world. Feeding by lunging open-mouthed into dense groups of such creatures, they can consume as much as 4.5 tons in a day. Water and food rushing into the whale's pleated, expandable mouth is forced past hundreds of wide, black fringed baleen plates that hang from the roof of the mouth. The plates act like a sieve or comb, trapping the solid food inside the fringes and expelling the excess water. Occasionally working in pairs, Blue whales have been observed weave through schools of krill, apparently using each other's bodies to block the escape of their prey.
Female Blue whales reach sexual maturity at approximately 5 years of age. They may give birth once every two or three years. Mating occurs during the summer season, and the gestation period lasts about 11 months. A single calf is usually born the following spring; twins are rare. The calves nurse for seven or eight months, gaining as much as 200 pounds per day in the nutrient-rich Antarctic or Arctic waters.
85 to 100 ft long