M@re Nostrum

Palabra de Ballena, por Cristina Cioffi
Word of Whale
By Cristina Cioffi
Translated by Guillermo Ramon Gil (FAMDIVER)

MARINE MAMMALS BIOACOUSTICS IN THE COAST OF ARGENTINA
EXPEDITION 71-3 OF THE INVESTIGATION SHIP HERO

ifferent communication ways exist among the cetaceans. They combine more or less amounts of chemical, tactile and visual signs, but acoustic signs are the most broadly used and the ones with a higher efficiency, even at long distances, through a single channel.

To be able to use that acoustic communication channel, a species should be able to emit some stimulus in this channel and to detect those stimuli with a specific mechanism. This way, we have a communication system.

Konrad Lorenz says: "there is only one psychology to set comparison systems. To enhance our knowledge about the human behavior we need, more than ever, to investigate that of the mammals, especially of those evolved ones. That observation demands enormous quantities of time and resources, and the results are not immediate.

We must consider about the history of the species today, we cannot delay the acquisition of that knowledge because it’s difficult to obtain. All the sciences somehow related to human behavior have the obligation to accept this new dimension."

That is: there is a narrow relationship between the human behavior and the behavior of the rest of mammals.

The study of communication evolution in Mysticeti is in a primitive state so far. This is because of the high amounts of resources, both of time and money, needed to follow a single animal in open water.

We could generalize anyway by saying that the number of fibers of the cochlear portion of a whale’s brain is many times bigger than that of the man. This amount of fibers is directly related with the acoustic abilities of the animal, so the whales have outstanding audition abilities.

These enhanced hearing abilities are supported by an impressive development of the parietal lobe of the brain and by a series of modifications in the inner ear that permit underwater audition.

This picture was shot a rainy day...Whales are corious by nature. Often the come close to the photographer with their impressive mass...One has to sail for years to have this picture... the reproductive organ of a big male.One can identify a whale from another by remembering the patterns of the callosities that form on their skin.
Some pictures of whales shot during this expedition... (clic to zoom)

INTERESTING DATA

By using a system of calibrated hydrophones, the expedition 71/3 of the oceanographic vessel Hero registered more than 200 low frequency sounds produced by whales in the San José Gulf, along several periods.

Most sounds were expressions similar to burps, with an average duration of 1.4 seconds and with frequencies ranging from 30 to 2,200 Hz. The original levels of emission were very high and ranged from 172 to 187 db/m2. Measurements were carried out on a wide spectrum, from 30 to 2, 200 Hz.

 Sonogram of a whale singing...

Whales also produced a series of different sounds, similar to groans, which lasted among 0.6 to 4.1 seconds. The groans extended up in frequency to 1,250 Hz. As in the burp sounds, groan sounds had the most energy below the 500Hz frequency.

During the investigations, a curious phenomenon was evident: “It has been observed that the gulls pick the whales, which suggests that they feed on the whale’s parasites. This interesting association should be studied in more depth. Picking gulls are of the species Larus dominicanus and Larus maculipinnis.

When the ship HERO, in charge of Capt. William C.Cummings, where James F.Fish, of the
Centro Naval Submarino de Investigación y Desarrollo, detected this association, they simply couldn’t imagine that a woman -20 years later!-, would achieve this picture. What a better coordination sample....


In the precise moment that the spiracle of the whale
blows water out, the gull picks her without leaning
her weight on, after a long and patient waiting time.

Golfo de San José, Patagonia Argentina             Capilla del Golfo de San José, monument to the early inhabitats that died in this inhospit place...
Some pictures shot in the Gulf of San José
(clic to zoom)


© Text and Pictures: Cristina Cioffi
© Translation: Guillermo Ramón Gil (FAMDIVER)

The drawing before the title was performed by  a 9 years old girl
after the author explained these experiences in a School of her country.

This article was given the

 

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Última modificación: 07 d’agost 2017 06:40


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