- Blue whales are the largest animals ever known to have lived on Earth, at up to 29.9 meters (98 ft) in length and with a maximum recorded weight of 173 tonnes (190 short tons)
- They occur in all oceans except the Arctic and enclosed seas.
- Their colouring is more blue-grey than blue with light grey or yellow-white undersides.
- A blue whale’s skin markings are unique, much like fingerprints
- Blue whales have relatively small eyes and their eyesight is thought to be weak
- They have a diet composed nearly exclusively of tiny shrimplike animals called krill. An adult blue whale can eat up to 40 million krill in a day
- Blue whales are usually alone or in pairs, but occasionally swim in small groups
- Populations migrate towards the poles, into cooler waters, in the summer to feed. They migrate back towards the equator, into warmer waters, in the winter to breed.
- They communicate using low-frequency whistles or rumbling noises. All blue whale groups make calls at a fundamental frequency between 10 and 40 Hz. The loudest sustained noise from a blue whale was at 188 dB
- Blue whales can reach speeds of 50 kilometres per hour (31 mph) over short bursts
- They typically swim at a depth of about 13 meters (43 feet) when migrating
- The average lifespan is estimated at around 80 to 90 years.
