Blue Whale: Habits, Diet and Other Facts

Blue whale (Balaenoptera musculus) is a mammal belonging to the family Balaenopteridae and the order Cetartiodactyla. The blue whale is known to be the largest animal in the world, measuring around 30 meters in length. Currently, this species is classified, according to the Red List of Endangered Species of the International Union for the Conservation of Nature and Natural Resources (IUCN), as endangered.

Blue Whale General Characteristics

The blue whale is an animal that arouses great fascination, especially for its body dimensions, being the largest animal on the planet. The largest specimen captured measured about 33 meters and weighed 190 tons. Below, we present some characteristics of this large mammal.

• The skin is blue-gray with white spots.
• They have a U-shaped head, measuring about a quarter the size of their body.
• They have ventral folds that can extend to almost half of the body. These folds help expand the crop to accumulate water and food.
• They have a short dorsal fin, located on the back of the body, measuring about 35 cm.
• They have between 270 to 400 pairs of black beards on their upper jaw. These beards are keratinized, can reach up to one meter in length and 55 cm in width, and serve to filter food. These whales have no teeth.
• They feed mainly on krill (a small crustacean), ingesting about four tons of this food daily.
• Its squirt, produced on exhalation, can reach 10 meters in height.
• Its longevity is estimated between 80 and 90 years.

Blue Whale Breeding

The blue whale generally lives alone, but it can also be found occasionally in pairs. The reproductive period takes place during winter and spring. The sexual maturity of this animal occurs around 10 years of age, when females are between 21 m and 23 m in length, and males, between 20 m and 21 m.

Females produce only one offspring per gestation. This lasts around 10 to 11 months and takes place every two to three years. The puppies, at birth, are between seven and eight meters long and can weigh around 2500 kg. The breastfeeding period for these lasts about eight months.

Blue Whale Distribution

The blue whale has a wide distribution, being found mainly in pelagic regions, generally below 100 meters in depth. They inhabit the most diverse oceans, being observed the existence of three subspecies in different regions: Balaenoptera musculus musculus, inhabiting the Northern Hemisphere; Balaenoptera musculus brevicauda, ​​inhabiting the sub-Antarctic zones of the Indian Ocean and the Western South Pacific; Balaenoptera musculus intermedia, inhabiting Antarctic regions.

The blue whale has a diverse migration pattern. It is observed that in summer and early autumn, called the feeding period, some individuals migrate to polar or subpolar waters. In winter and spring, known as the reproductive period, they migrate to tropical or subtropical areas.

In this process, it is observed that some individuals make long migrations to food areas, while others migrate to more limited areas. However, it is also observed that some individuals remain throughout the year in areas of greater productivity.

Blue Whale Threats

For many years, the hunting of blue whales was intense, bringing the species almost to extinction. In 1966, the International Whaling Commission (CIB) started to protect this species, and its hunting was stopped in the 1970s.

However, some problems still affect blue whale populations, such as habitat degradation; the intensive fishing of its biggest prey, the Krill; accidental captures; and collisions with ships.

Public preservation policies are essential, not only for this species, but for the environment as a whole, in order to preserve as many species as possible and the well-being of all populations.

Blue Whale Fun Facts

• The baby blue whale ingests about 600 liters of milk daily.
• The blue whale swims at an average speed of eight km/h and can reach 30 km/h.
• Blue whales communicate by emitting low frequency sounds.
• Blue whales have a very sensitive hearing, being able to hear the sounds emitted by another whale that is up to 1600 km away.