Although there are no extinct dinosaurs today, there is a creature that is as big as them. The blue whale is currently the largest animal in the world, with a length of more than 30 meters. A real giant, but that may not be enough. Also known as the sky whale, this creature is a marine mammal. It belongs to the Mysticeti (toothless whales) suborder of the Cetacea (whales) order and its scientific name is Balaenoptera musculus.
In this article, we will give you interesting information about the blue whale.
This creature, also known as the sky whale, is a marine mammal. It belongs to the Mysticeti (toothless whales) suborder of the Cetacea (whales) order and its scientific name is Balaenoptera musculus.
Blue Whale Physical Characteristics
The blue whale's head is flat from the side and U-shaped from the top. It has two rather large breathing holes. When it breathes out from these holes, it can spray to a height of 6 to 12 meters. There are 60 to 90 grooves running parallel from the neck to the abdomen. Thanks to these grooves, the blue whale's throat expands incredibly, making feeding easier. Another function of these is to reduce water resistance while swimming.
The blue whale, which appears blue or gray from the top, has a long body that tapers towards its tail. Its dorsal fin is small and can usually be seen when diving. The pectoral fins are approximately 4 meters long. The caudal fin, which is wide and triangular in shape, is plain gray in color. It has a spotted back structure and the front of the mouth is thick. The animal's neck has a whitish color. Since it is very soft, the head and neck area can be easily hit.
It is estimated that even the largest known dinosaur, Argentinosaurus, could reach a maximum weight of 90 tons. It is very difficult to measure giant blue whales. Sky whales were measured not as a whole but in portable pieces. If we include all subspecies, the average length of blue whales is about 25 m and the average weight is about 115 tons. The largest blue whales on record are 45 meters long and weigh between 300 and 450 tons.
The body of blue whales, which feed on microorganisms called diatoms in the cold waters of the North Atlantic and Antarctica, is covered with a thin layer of diatoms and its lower surface appears to be yellowish green or orangey brown. This is the reason why ancient whalers called sky whales sulfur-bottomed whales.
Reproduction in Blue Whales
Male blue whales reach sexual maturity when they are 10 years old, and females at 6 years old. The breeding season continues from autumn until the end of winter. They give birth to a single offspring every 2-3 years and after a gestation period of approximately one year.
The cub is breastfed for 7 months until it reaches an average height of 16 meters and weighs 20 tons and enters the weaning period. The lactating kitten absorbs approximately 400 liters of milk every day; While his weight increases by 90 kg per day, his height increases by approximately 4 cm. Baby blue whales develop very quickly and become able to survive on their own in 7 months.
Social Structure in Blue Whales
Blue whales are distributed in all oceans except the polar regions. They mostly live alone or as a mother-cub pair. They may gather in scattered communities of up to several dozen in feeding areas.
They communicate between individuals by making various sounds. Apart from this, they may also exhibit behaviors such as jumping to the surface or sticking out their tails.
Blue Whale Species
Blue whales are divided into three subspecies.
▪ B. musculus musculus: Northern Pacific Ocean and North Atlantic
▪ B. musculus intermedia: Antarctic environment and the Southern Ocean
▪ B. musculus brevicauda: Southern Pacific Ocean and Indian Ocean
Some experts considerB. Another species native to the Indian Ocean called musculus indica is also considered a subspecies.
Population of Blue Whales
The population of blue whales, which is considered a threatened species by the International Union for Conservation of Nature and Natural Resources, is estimated to be between 5000 and 12000, according to a study conducted in 2002.
Sound of the Blue Whale
The blue whale is the loudest animal in the world after the sperm whale. It has been measured that they can produce 155-180 decibels (dB) of sound in water. The equivalent in air is equivalent to a sound range of 89-122 dB. Considering that an air drill produces approximately 100 dB of sound, we can understand the situation better.
Although they can make such loud sounds, it is not possible for humans to perceive this sound. Because:
All populations of blue whales make sounds in the frequency range of 10-40 hertz (Hz). The lowest frequency that a human can perceive is around 20 Hz.
The calls of blue whales generally last between 10 and 30 seconds. Some sky whales observed off the coast of Sri Lanka have been recorded to repeat songs consisting of four notes that can last up to two minutes.
Scientists have not yet figured out why blue whales call. He focuses on six possibilities in this regard:
Maintaining distance between individuals
Recognizing species and individuals
Transfer of information such as nutrition, courtship, warning
Preservation of social order
Transferring location information
Identification of prey resources
What Does a Blue Whale Eat? How to Eat?
The blue whale eats small crustaceans called krill. They open their mouths to feed and filter sea water. Small fish and squids that feed on krill while feeding may also be swallowed by the blue whale. Contrary to popular belief, whales cannot eat humans.
Because the whale's throat is not large enough to swallow any human. In other words, in order for whales to eat humans, they must first have teeth that can be used to tear apart people.
The esophagus of blue whales is quite small compared to their size. These features allow them to survive by consuming much less food. They can spend 7-8 months of the year without eating anything. As a result of research and observations, it has been determined that they only feed during the summer season.
During the feeding season, the whale can consume an average of 40 million krill, 2-4 tons per day. Food availability is the main factor determining the distribution of blue whales in the seas. They prefer to feed on the densest krill swarms they can find. Krill migrate daily to the surface at night to feed on phytoplankton. Whales also follow this migration to hunt krill. For this reason, they can be seen both in coastal waters and in the open sea.
Why Does the Blue Whale Migrate?
Blue whales migrate seasonally during the spring months towards the poles, which are very fertile in terms of food. In autumn, they move to sub-tropical regions to avoid being stuck in the ice, to consume less energy and to reproduce. Blue whales are strong and fast swimmers. Normally they swim at a speed of 20 km per hour, but when necessary they can accelerate to 50 km.
How Long Does a Blue Whale Live?
The average lifespan of humpback whales is 45 - 50 years. Killer whales live 25 to 30 years. It is thought that blue whales can live much longer than other whale species. The lifespan of a blue whale is estimated at 80 years, but the longest recorded study to date covers 43 years.
Blue whale strandings are a very rare event, and the mass strandings observed in dolphins have never been seen. Its natural enemies are humans and killer whales.
