Blue Whale Facts

The blue whale (balaenoptera musculus) is part of the (mysticeti) baleen whale suborder and is the largest animal alive growing as large as 100 ft. in length and weighing as much as 150 tons or more.

In addition to their size they are also one of the loudest mammals in existence and can be heard many miles away.

Some scientist believe that blue whales use their sound not only for communication, but also for echolocation and are looking into the possibility of echolocation playing a role in helping these whales better navigate the ocean.

Surprisingly as compared to their massive size these whales primarily eat krill which resemble small shrimp.

These marine mammals travel an average of 3 – 12 miles per hour, but can reach speeds of over 25 miles per hour when they feel threatened or agitated.

Other than humans (many countries have adopted policies against hunting whales) blue whales are rarely attacked by other animals.

On rare occasions blue whales may come under attack by sharks or killer whales.


Blue whales primarily eat krill although other small ocean creatures such as copepods can be ingested as well.

Blue whales are almost always found in area’s with high concentrations of krill.

The method blue whales use to capture and consume their prey is known as “filter feeding“.

These whales hunt for their food by opening its mouth, lunging at the krill and ingesting large amounts of krill and water.

As they ingest the water the small krill get stuck in the whales baleen plates.

The whale than expels the water by pushing it out with its tongue and swallows the trapped krill.

Physical Characteristics

At the surface blue whales are actually a greyish blue color although they appear purely blue underneath the water.

Blue whales can grow to be over 100 ft. long (average is around 70 – 80 ft) and weigh more than 150 tons.

Compared to their length their bodies are generally slim and streamlined for speed and long distance travel allowing them to swim up to 25 miles per hour or more (average speed is closer to 5 mph).

The blue whale also has a very small triangular dorsal fin as compared to the larger dorsal fin of many other whales and short flippers which only measure about 12% of the whales length.


Blue whales can be found swimming throughout the worlds major oceans.

These whales will migrate towards colder polar waters during feeding season and warmer tropical waters during mating season and can travel thousands of miles during their migration.

While they migrate most whales will forgo eating food and live primarily off of body fat and stored calories.

Migration trips can last for up to 4 months depending on where they are traveling from and going to.

Older, pregnant and sexually mature whales typically travel first and furthest during migration due to experience and excess body fat which allows them to deal with colder waters more effectively than younger whales.

Social Structure

Blue whales are solitary animals often traveling alone or in small groups.

They communicate to one another by using loud low-pitched sounds which can be heard many miles away.

Although they prefer being solitary blue whales can be found traveling in larger groups during periods of feeding and migration.


Little is known about how blue whales reproduce.

Females breed on average every 2-3 years.

Birth usually takes place 10 – 12 months after mating.

Blue whales usually mature around 8-10 years of age.

When they reach adult hood the female whales grow to be larger on average than their male counterparts.

10 Interesting blue whale facts

  1. Being able to grow to lengths of over 100 ft. long and weighing up to 180 tons the blue whale is the largest living animal in the world.
  2. Although the blue whale is called a “blue” whale it is actually closer to a grayish blue rather than a solid blue. It isn’t until the whale dives under the water that it appears to be a solid blue color.
  3. A baby blue whale can measure in at around 25 ft. long making it as big as a killer whale, which is the largest marine mammal in the dolphin species.
  4. A healthy adult blue whale can live for 70 – 90 years.
  5. The blue whale can eat as many as 40 million krill per day or around 8,000 lbs. daily in order to power its massive body.
  6. These marine mammals aren’t known to have any natural predators, except for occasional attacks on smaller (usually) baby whales by a pack of killer whales, however these attacks appear to be quite rare.
  7. When searching for food the blue whale can hold its breath for up to 35 minutes.
  8. Depending on where the research has been gathered it is estimated that as much as 95% – 99% of the entire blue whale population was killed during the whaling era.
  9. Due to significant hunting during the whaling era these marine mammals are now considered endangered and are listed as a protected species.
  10. The blue whale belongs to one of around 80 known species is Cetacea, which includes all species of whale, dolphin and porpoise.