HomeDiscoveryAnimal speciesBlue Whale
Blue Whale

Queue Rorqual Bleu

print send digg delicious
  • Présentement 2.49/5 étoile.
  • 1
  • 2
  • 3
  • 4
  • 5
comments 0 comment

Blue Whale

Family: Balaenopteridae
Length: 26 m
Weight: 120,000 kg
Sexual maturity: 5 years
Lifespan: 40 to 50 years

  • Long slender body
  • Bluish grey back with lighter markings
  • Underside ivory and blue-grey
  • Underside of flippers whitish-coloured
  • Small dorsal fin

The blue whale (Balaenoptera musculus) is the largest animal on Earth, rivalling the largest known dinosaurs in both weight and length. This baleen whale travels in all the world’s ice-free seas and oceans. The Saint Lawrence River is one of the rare places where the blue whale can be observed close to shore. 

Super-sized creature

Rorqual bleuOn the blue whale, everything is enormous. Its tongue weighs 4,000 kilograms. Its heart is the size of a small car. Its mouth can hold 50,000 litres of water, the equivalent of a backyard swimming pool. Its stomach can take in 1,000 litres of food.

 

Diving

The blue whale dives to depths of up to 200 metres. Dives generally last from ten to 30 minutes, but can extend for up to about 50 minutes. When resurfacing for fresh air, it expels a blow that can reach nine metres in height.  

Ventral pleats

The skin beneath the blue whale’s jaw is expandable in a way similar to the pelican’s pouch. These pouches, or “ventral pleats” extend from the chin to the navel, and consist of flexible folds that expand when the whale takes in a mouthful of water teeming with food.  

Krill trap

Baleen hangs from the upper jaw and consists of fingernail-like blade-shaped plates and rigid hairs. Baleen acts as a filter, letting water escape the mouth while trapping food within. Each day, the blue whale consumes between 2,000 and 4,000 kilograms of krill.

Social life

Rorqual bleuThe blue whale tends to be solitary, but also lives in small groups of two to four individuals. The biggest gatherings take place when the whales converge on a shoal of krill, and during mating season.

Reproduction

Mating occurs during winter in warm and tropical waters. The whales then spend the whole summer in Arctic or Antarctic waters. The following winter, after a gestation period of ten to twelve months, the whales return to temperate waters to give birth. Every two or three years, the female gives birth to a single calf, or very rarely two.

Gargantuan babies

At birth, the calf is seven metres long, the length of a school bus, and weighs 2,000 kilograms, as much as a minivan. Feeding on its mother’s rich milk, of which it drinks 200 to 400 litres a day, it grows very rapidly, gaining about four kilograms an hour, or over 90 kilograms a day!

Predators

The killer whale, which can attack the young, is the blue whale’s only predator. This giant cetacean also occasionally dies after colliding with a ship or becoming entangled in a fishing net. Blue whales also occasionally become trapped in ice.

Population decimated

Rorqual bleuAt the beginning of the 20th century, the worldwide blue whale population was over 200,000 individuals. However, intensive whaling soon led to a major decline in the numbers of these peaceful animals. In 1931 alone, 30,000 blue whales were killed. With today’s population of about 10,000 individuals, the species is considered threatened.

Related articles
21 - Blue Behemoths in the Sea of Cortés
Biologist Diane Gendron studies our planet’s largest living animal: the blue whale.
30- Call of the Sea
Richard Sears studies rorquals in the majestic setting of Quebec’s Mingan Archipelago.
Links
Whales on-line Reference site and news dedicated to education for the conservation of whales in the St. Lawrence and their natural habitat.
Leave a comment


Remove image Images must be in JPG format and not exceed 10 MB.
Resolution must be less than 3,000 by 3,000 pixels.


Authentication
Enter the characters appearing in the image above. If you’re unable to read them, please click here.

Search
Games
dhpsb Marine Mammals
Nature photography game. Can you pilot the Gizmo Lab?
dhpsb The Little Lost Whale
Logic game. Can you help the whale calf find its mother?
promo