Whales are the largest aquatic mammals that exist. Basically they are cetaceans that have many shapes, colors and sizes, they are characterized by large migrations, they have been hunted to the point of extinction for their multiple commercial uses and today there are organizations concerned with their conservation. If you want to know more about them, we invite you to read this article.
Whales (Balaenidae)
The balenids (Balaenidae) form a large family of mysticete cetaceans that includes only four species that will be named in the following sections of this article, which are included in two genera, which are Balaena and Eubalaena.
However, the word whales is used in a broad sense to refer to all the large cetaceans, included in the parvorder Mysticeti, or baleen cetaceans, such as the blue whale (Balaenoptera musculus) and several species of the parvorder Odontoceti, which are toothed cetaceans. , as is the case of the sperm whale (Physeter macrocephalus).
Taxonomy
- Animalia Kingdom
- Edge: Chordata
- Subphylum: Vertebrata
- Class: Mammalia
- Order: Artiodactyla
- Suborder: Whippomorpha
- Infraorder: Cetacea
- Parvorden: Mysticeti
- Family: Balaenidae
- Genders:
- Balaena Linnaeus, 1758
- Eubalaena Gray, 1864
Etymology
The word whales, which basically comes from the Latin ballaena, which is rooted in the Greek phalaina, is of uncertain etymology. It would have an unknown meaning if it came from some previous Mediterranean language, or, in the case of being of Indo-European origin, perhaps Illyrian, it could refer to its cylindrical or swollen shape, which is particular to this family.
These animals were also called by the name of Cetus, the great fish, the Leviathan or the sea monster. Baleen whales, which are actually keratinous sheets that allow them to filter food from the water, are also called whales, which are known in English as baleens.
Characteristics of the Whales
These are mammals that have a long skull that can be up to a third of the total length of their body, which in adulthood can measure between 15 and 17 meters and weigh between 50 and 80 meters. tons. They have a narrow and arched maxilla, which gives these animals a convex profile. This maxillary design is what allows the presence of long beards, which can measure between 5 and 25 meters in length.
Unlike fish, whales have a tail that is placed horizontally, whose function is to facilitate their rise to the surface, which they must rise to breathe, although they are capable of remaining submerged for up to an hour below. the water also puts half of their brain to sleep so as not to sink. They have two spiracles or nostrils, which are located on top of the head, through which they manage to expel water along with mucus on many occasions.
The gestation of the whales lasts about 12 months and they usually give birth to a single calf, which feeds on a mother's milk that is particularly loaded with nutrients. Their life expectancy is about 30 years. They are characterized by large migrations from the cold oceans, where they feed, to the warm oceans, where they mate and reproduce. They are cosmopolitan and also pass through the Mediterranean.
Their diet consists of small crustaceans, mainly copepods, although some species also eat a large volume of krill. They have a stocky or bulky build compared to rorquals, and lack gular folds and a dorsal fin.
Whales are not fish, because they have warm blood, they breathe air because their respiratory system is pulmonary, and they give birth to live young that feed on their mother's milk. They have an excellent hearing system and are two to three times more efficient than land mammals at using the oxygen in the air they breathe.
Whales have rib cages that are collapsible, which can help them when they dive to great depths. In addition, they have a very thick layer of fat that gives them the necessary insulation to protect them from the cold. This was the reason why they were so coveted for the large amount of oil they could produce.
Scientists think that whales evolved from land mammals that had four legs. Now, they are perfectly adapted to underwater life. They have a streamlined body and have practically lost almost all of their external hair to avoid friction and improve movement in the water. Thanks to evolutionary adaptation, their limbs became fins.
As we have already said, there are two main types of whales, the toothed ones such as the sperm whale and the orca, and the baleen ones such as the humpback and blue whales. The beards have plates in the form of combs that are made up of structures composed of hairs that are rigid. These constitute a network for the food to be filtered from the sea water. A significant portion of the great whales are baleen and feed essentially on tiny creatures called krill, which resemble shrimp.
Preservation and Conservation
With the aim of achieving the conservation and preservation of whales, an organization was established in 1948 that was called the International Whaling Commission (CBI) as an entity that is in charge of regulating the operation of the International Convention for the Regulation of the Whaling, which was signed on December 2, 1946 in Washington DC United States.
The objective of this convention was to guarantee the conservation of the whaling populations, as well as to make possible an appropriate development of the industry that uses whales as raw material. The treaty was originally made up of 14 countries, but today it has around 84 members, in which a focus on the conservation of the species has been chosen.
Unfortunately, the different perspectives that exist between the countries have caused impediments so that different initiatives can be implemented, such as the whaling sanctuary of the Indian Ocean and the South Pacific.
The main objectives with which the creation of this organization was proposed were to implement the policies of conservation and preservation of small and large cetaceans, the regulation of voluntary fishing and the reduction of accidental fishing of the same, as well as the care of the marine ecosystems in which these organisms develop.
In addition to this, we find ourselves with a fundamental problem in this organization. There are member countries with extensive whaling industries, such as Norway, Japan and Iceland, which are still carrying out large-scale killings of whales, although they say their programs are based on a type of scientific whaling.
It has been proven that Japan has taken on the task of financially financing other member countries, under the premise of being able to count on the possibility of doing so in exchange for their vote in the organization, practices that have made it impossible to obtain a majority of three-quarters of the membership is needed in order to implement significant changes to current conservation policies, creating a situation of paralysis, in which practically nothing can be done.
Commercial exploitation
Whaling began in the XNUMXth century, in the Bay of Biscay, by Basque fishermen, and until the XNUMXth century it was limited to the right whale or right whale in English, which receives that name due to the ease with which it is hunted. could capture, because its movements are slow and because it has a lot of fat, which is why it floated after it was killed and this facilitated its dragging.
The technological improvements that have been implemented in boats and the invention, in 1877, of the explosive harpoon, gave rise to excessive hunting that brought many species of cetaceans to the brink of extinction. In 1949, the International Whaling Commission was created as an attempt to limit the capture, and since 1985 the suspension of commercial hunting was established.
However, Japan and Norway oppose the agreement, and continue with the hunting activity with the species that they consider are not in danger of extinction. To try to mitigate the danger that whales are in, synthetic products have been created that have replaced some products that were obtained from whales, such as oil.
Thanks to the new sensitivity to the environment, a kind of tourism has been developed, called whale watching, particularly in places where these animals are concentrated, such as the Argentine Patagonia.
The Whale in Culture
Whales always appear as a kind of sea monster that attacks men in stories and tales from different cultures. A story that is known worldwide is the one about Moby-Dick's aggressive whale, who is also known as Mocha Dick, and who becomes an obsession for the protagonist in the novel. However, we have also observed it as a concern for man.
Currently, we can find that there are multiple organizations that aim to conserve and protect this animal species. As a curious fact, in 2016 Argentina issued a bill with the denomination of 200 pesos, which has the image of the southern right whale.
Threats
One of the great threats to whales is the pollution of the oceans by the dumping of toxic waste from industrial, agricultural or domestic origin, which endangers the conservation of all marine animals.
There are contaminants that persist in the water, such as organochlorine pesticides and polychlorinated biphenyl PCBs, which unfortunately are ingested due to their food chain, with the aggravating circumstance that they are bioaccumulative and biomagnifiable, because they manage to accumulate in the fatty tissues of cetaceans, which it affects your immune, endocrine, and reproductive systems.
The damage that occurs in their immune system puts the whales in danger of suffering from any disease, as well as making them susceptible to biotoxins or the attack of viruses or bacteria that would not be harmful to them in other circumstances.
Another aspect to take into account is that the contamination of the seas creates the ideal conditions for outbreaks of red tide, whose biotoxins have already caused the massive death of marine organisms, including whales.
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