| Whale Stories |
By: Prof. Fabio German Cupul Magaña - Official Member
of the Mexican Society for the Divulgation of Science and Technology SOMEDICYT
November 2005 |
 The humpback whale, in contrast to other herd whales, lives in groups of constant change, made up of four to ten members. The most stable relationship of these animals is found between the mother and her off-spring. They stay together for almost one year.
Generally the humpback whale gives birth to one young which comes out with its tail first. The short umbilical cord breaks and the newly born swims towards the surface of the water in order to breathe for the first time. The mother pushes the newborn upwards with its snout or with one of its fins. These first seconds are vital for the huge baby whales because until their lungs are filled with air, their body will be heavier than the water and there is the risk of sinking and drowning.
Throughout their growth and in their adulthood, the huge whales carry out movements that we could interpret as "games". They jump out of the water covered by a cloak of spray, in order afterwards to rotate in the air with elegance and to fall back into the ocean with a loud noise, spurting up a stream of water to announce their plunge. When they return to the surface, minutes later, they twist lazily and hit the water with their fins.
 Subsequently they submerge lifting their enormous tail, which they let fall with such force that it produces a racket which can be heard from a distance of various kilometers. Even though this behavior can be interpreted as a play, it is believed that the hitting of the water is a form of communicating with those of their own specie or it could also be related to the search of food.
On the other hand one of the fascinating aspects of the whales is their capacity to retain air during large periods of time. For the baby whales the average time is between 30 and 40 minutes, however they can hold out for up to 2 hours under water.
But instead of sustaining themselves without breathing, the beluga whale of the Artic uses unusual techniques in order to be able to survive under water. The males migrate up to 800 km under blocks of solid ice on the surface, but their lungs are not bigger than ours and they barely can hold their breath for a maximum of 20 minutes. Therefore it is difficult to understand how they do it.
 The above mentioned secret has to do with the strange and characteristic sound which is produced by water made in the holes on the surface ice. In each immersion a beluga whale can travel 2 km under the layer of ice until perceiving the characteristic sound and locating the hole through which it will come out to take in air. In order to prevent drowning, the whale retains enough air in order to be able to return to the last hole in case of an emergency.
Another fact that awakens the interest of society and of the scientists is the stranding of the whales on the beach. Every year between one and two thousand whales loose their lives stranded on the coasts. This phenomenon happens to a very few species and all of them have something in common: they live in groups of great social coherence. Therefore if the leader gets stranded, the others tragically follow him. Their strong ties of friendship apparently surpass any individual desire for salvation.
A combination of factors seems to be the result of these strange sacrifices and the majority of the explanations include some type of navigational accident. The coastal species, familiarized with the local environment have a low probability of getting lost. Therefore an infection or disease in the inner ear is the most viable explanation for their collective deaths.
 Nevertheless, the open sea species, less familiarized with the shallow waters of the coast, could easily make fatal navigational mistakes. Their sonar could be confused by the long and inclined beached and the mistake could even be in the magnetic navigational system. The stranding usually occurs on beaches where the magnetic "highways" turn towards the coast. Probably the whales use the magnetic lines of the earth to find their way in the ocean. Following the lines of the coast during their travels, they may realize their mistake too late, when the waters are already so shallow that it does not permit the whales to turn around and escape their certain death.
Prof. Fabio German Cupul Magaña
E-mail:
fcupul@pv.udg.mx
The publication of this article is possible thanks to the authorization of Prof. Fabio German Cupul Magaña, author of the books "Tales of natural history in Vallarta - University of Guadalajara" (Relatos de la historia natural vallartense - Universidad de Guadalajara) and "Natural environment: Selection of essays of scientific disclosure - Coastal University Center of the University of Guadalajara". (Ambiente natural: Selección de ensayos de divulgación científica - Centro Universitario de La Costa Universidad de Guadalajara).
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