Coral Mystery pt X Biology br Dott.ssa Margherita Superchi

Coral Reproduction
The genital organs of coral are located inside the polyps and they have different genders in the sense that there are both male and female colonies. In some cases we also noted the presence of hermaphrodite colonies, created by  the fusion of two colonies.
The maturing of the male reproductive cells occurs after one year while for females 2 years are required.
How does reproduction take place? By fertilisation of by larval reproduction.
Fertilisation: following emission from the male polyp, the spermatozoa navigate looking for a female polyp to fertilise.
The mechanism of attraction is still a mystery.
Fertilisation then takes place inside the female polyp.
The young larva, called planula, develops in approximately 20/30 days before exiting into the open sea.
This process usually occurs during the month of June.
In the future this will involve a number of considerations – which will certainly arouse polemics – regarding the possibility of fishing before the new organisms, the planulae, are born.

Larval Reproduction: The planulae leave the mother polyp and wander through the waters looking for a hard and rocky substratum upon which to deposit. Once they find it, a new miracle takes place: the mouth with its eight tentacles positions itself to collect food, the first gastrovascular canals develop and in about twelve days, what will be the skeletal axis begins to form…the skeletal axis is the interior of the branch, the calcium carbonate skeleton, and in about 2/3 days it gradually becomes red.
What had originally been a planula begins to feed and grow, to swell like a large pimple: and this is when a second polyp appears!
From this moment on the two work to secrete, building the skeletal axis that will be fully formed in six months!
Thus from larva to larva, polyp to polyp, the coral branch grows and develops. As we can see, all the vital functions of a coral colony are in the sarcosoma, the external part of the polyp.
If all the coral of Sciacca, as noted by many, suddenly appeared without a sarcosoma, what would this mean? Indubitably and unquestionably that we are in the presence of dead coral, my friends, of which only the skeleton remains, and we don’t even really know why...

to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt IX Biology by Dott.ssa Margherita Superchi

They also studied the “foods” preferred by the polyp colonies. And do you know what they like to eat? Shrimp! Naturally, tiny, microscopic shrimp contained in the plankton!
Today we can say that we know much more. But let’s get back to the structure of the polyp.
The polyp is the structural unit of the branch: viewed in its entirety, it is shaped like a delicate white flower, transparent, with its eight petals swaying in the current and indicative of how and why its animal nature has for so long been ignored.
It is the polyps that provide nutrients to the colony, using their long tentacles to capture tiny particles of plankton fluctuating in the water and by swallowing dissolved substances also found in the water.
These substances circulate internally by internal secretion and cause the axial skeleton to grow. In fact, if you cut through a branch you can actually see the concentric circles of growth.
The times of opening/closing of the polyps have been studied and apparently they respond to the demand for food that comes from the colony: the hungrier it is the longer the polyps remain open.
The growing times of a colony vary from zone to zone, subject to subject and are closely linked to the quantity of food present in the water as well as the number of other colonies present within the same area.
Just think that in the zone of Portofino, on a single bank, in a surface area of just one square meter, we counted more than one thousand colonies.
Given the crowding it is clear that it would be highly difficult for any of the coral branches to reach any great size. To give you an idea, think of a forest: wherever the trees are overly abundant they rarely grow tall and robust. But if there are only a few, and if they manage to feed well, then they can become splendid corms.
Since the causes of growth are too numerous and too diversified, I must confess that studies of such aspects have yet to provide universally valid results. Considering the numerous studies that have been undertaken (especially HARMELIN) we can risk giving a vertical growth rate of 6-7 mm per year for young colonies and 3-5 for colonies with secondary ramifications.
Why does coral ramify? In my modest opinion, in order to collect more food by having multiple mouths in different positions.
Why are there branches that are nice and smooth and others that are, well, rather contorted?
That depends on where the colonies are located and on currents. A unidirectional current will give a nice smooth coral (like the ceiling of grottoes); a variable current provides a rougher coral, rather like a bush.
In order to anchor itself to the bank, coral needs a rigid substratum. Naturally it prefers zones that have a coral substratum, formed of calcium concretions but it can also attach itself to mud and sand.
We should also keep in mind that coral grows where there is little or no light. So that in shallow areas it grows wherever there are grottoes or ravines while at greater depths it can be found in open areas.
Another important fact is that coral prefers waters that are not necessarily calm but where the marine currents do not cause violent eddies or whirls.
Inversely, a total absence of marine currents does not allow coral to live as there is no “passage” of food. As for pollution, if there is little contamination coral tends to grow while it cannot live at all if the waters are contaminated.

to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt.VIII Biology by Dott.ssa Margherita Superchi

 This is its identification card:
scientific name:    Corallium rubrum
phylum:         Cnidaria
class:         Anthozoa (Animal flower: from the Greek     “ἄυθος/anthos” flower, and “ζῷον/zoon” animal)
subclass:         Octocorallia
order:         Gorgoniaceae

The Cnidaria is divided into 4 classes, one of these being the Anthozoa class which comes in the form of a polyp and is in turn divided into 2 sub-classes, according to the number of tentacles:
Hexacorallia (6 tentacles or multiples of 6) include reef corals, found on barrier banks, and commonly called madreporaria, sea anemones, black coral and gorgonacea.
Octocorallia, this is the coral we work with: Corallium rubrum, Corallium japonicum and another 27 species of coral.

Anatomy of Red Coral

The anatomy of coral is relatively simple, and is composed of:
- polyp colonies
- skeleton
- external surface

Regarding the polyp colonies: the small polyps with eight tentacles live in colonies, inside the skeleton, and transmit information, sensations, food, etc. through a system of canals in the external surface.
Too simple? I can provide some additional data.
The small polyps are in contact with the external world. They live in the water and from water they receive nutrients but are also subject to its dangers: fish, parasites, storms, volcanic activity, this we have seen, correct? It is also the polyps that take nutrition from the water, the plankton, which they digest and that is used to increase the skeletal axis.
Then there is what for the sake of simplicity we have called the external surface of the polyps but that we must of necessity call by its true name: sarcosoma. What is this? The sarcosoma is the whole of the tissues that cover the axial skeleton just like a glove covers a finger. The skeleton therefore is made from an external secretion. The skeleton of coral is entirely mineralised as it is composed of calcium carbonate, crystallised in the form of calcite. Inside the skeleton there is a network of canals very similar to the circulatory system.
It is through this system of canals that all parts of the skeleton are fed and all information is passed to the entire colony of polyps.
In fact, if we try to touch a single polyp, even a peripheral one, the polyp recognizes danger and conceals itself from view by completely contracting within its cavity, as will all the polyps of the colony: indicating that the information is immediately filtered from polyp to polyp.
Therefore we cannot consider the polyps as living autonomously within a colony but as mouths through which the coral feeds and maintains contact with the outside world.
We have already mentioned the “Red Coral” research group composed of more than 20 Universities and Marine Biology Institutes from all over Europe. These scientists divided their research on coral into individual tasks and studies, to acquire more knowledge, until then very limited, on how it grows, reproduces and feeds.
One member who has done much in the sector of nutrition is the Naples Zoological Station “Anton Dhorn”, through the Ischia Section at the time directed by my dear friend Gianni Russo.
Dhorn retrieved colonies of coral from the sea and placed them in a tank. He then performed extensive studies on the opening and closing of the polyp colonies and noted that they all expanded, that is the polyps come out when they are hungry and re-enter the sarcosoma as soon as they are sated. One would think for a short nap...

to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt.VII the Study

 

The Second Technical Meeting on Red Coral of the Mediterranean was thus held in Torre del Greco at the end of September 1988.

the final document states “it is indispensable, for purposes of an exact assessment of coral, to carry out a systematic inquiry and a precise evaluation of the resources of red coral in the entire Mediterranean area.
“Only after such an inquiry can we determine whether red coral is truly about to become extinct.
“Scientists must undertake a series of studies on how and in what quantities coral grows in the various geographic areas, on the phenomena that delay its growth (pollution in primis), the criteria, if there are any, for its reproduction in laboratories or by breeding.
“Only after we have this data will it be possible to ensure a rational exploitation of the resources and a balanced rotation of fishing zones that also considers the supply needed for manufacture.”
It was on this occasion that they established the basis for the “Italian Group for Coral Research” whose enthusiastic members included about twenty Universities and Marine Biology Institutes. Fabio Cicogna was appointed coordinator, having done everything possible to ensure the success of the Consultation. Another member was the Oceanology and Paleoecology Institute of the University of Catania, which assumed the task of studying the Coral of Sciacca.
Under the leadership of Prof. Italo Di Geronimo, Professors Antonietta Rosso and Rossana Sanfilippo did some excellent research, both at sea and in the laboratory. Meticulous, accurate and difficult work. This is the final report:
“...in conclusion, based on the data emerging from this research and in literature we can formulate some initial theories on the possible origin of the coral banks of Sciacca. Specifically:
“In the area of the Sciacca banks there are submerged reliefs of volcanic and sedimentary nature, that could host or could have hosted red coral.
“The fossil banks exploited in the last century appear to be related only to submerged reliefs of volcanic origin while there is no indications of dead red coral around the other reliefs.
“This fact could be related to the scanty cohesion of the tuffite that composes the volcanic structures and that in the presence of occasional strong currents or even small seismic movements, could be subject to fragmentation, slides and falls that result in a continutous, and sometimes large accumulation of matter at their base. A ring of mixed organogenic and inorganic debris, rich in fragments and colonies of red coral, which could also slide into the surrounding bathyal mud would form an underwater bank.
The ingegni of the previous century would fish inside these rings around the submerged structures, scattering the material that the dredges could not grasp along the bottom as it was dragged, thus enlarging the area of the “bank”.
The more superficial, and youngest, material extracted was generally of better quality than the lower layers, regardless of when it was buried.
The oldest layer of red coral could be very old but almost certainly not antecedent to the last glacial period (about 18,000 years ago) because no fauna characteristic of a cold environment were found in the thanatocoenoses.
Further studies could clarify the origin of the Sciacca banks. In particular, it would be interesting to attempt to reconstruct the recent sediment stratification of the area, using absolute dating on the skeletal remains. Such a study would give a more detailed idea of the time required to form the Sciacca banks.”
It was an invitation! They had done an excellent job in Catania, but – as they themselves admit – further studies and tests were required. They had turned on a light in my head that I just could not turn off...

to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt.VI the Study

About the second bank, the one discovered in August 1878, Canestrini observes that “it too is approximately 200 meters deep, according to our sounding lines, and is covered in mud, as was evidenced by the dredging performed on site. It is more extensive than the previous one, as the length is approximately one mile and about ¾ of a mile in width. It still contains a moderate quantity of coral even now, as proven by the fact that on 26 and 27 July there were between eighteen and twenty trawlers fishing. The presence of this quantity of coral was also demonstrated by our dredging, which revealed that it was of excellent quality, as it is generally of a beautiful red color and only a small quantity is darkish or black. We may presume that during this year the bank will be so exploited that any future fishing will not be worth the cost of the undertaking. Here too we found that all the coral lacked a sarcosoma, that it is dead, and so there is no hope that it may grow or reproduce.”
Of the third bank, the one found in 1880, Canestrini writes: “of the three it is the most extensive, as its length may be assessed at 2.5 miles and its width is 2 miles. It is approximately 180 meters in depth, oscillating, according to our depth sounders, from a minimum of 148 metres to a maximum of 200 meters.
“It too, like the other banks in the area, is covered in mud.
“The coral we collected there was dead, and we also gathered some other animal species found on the other banks. As for the quantity of the coral, we can say it was significant, because even this year there are approximately 200 trawlers fishing, and we collected a significant quantity with our own nets. But the quality is very poor; the tiny shrubs are generally short and thin and the color tends to be blackish, thus the commercial price of this coral is rather low. It is highly likely that in a few years fishing on this bank will no longer be profitable and will be abandoned.”

to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Lost Island is back

Hi Divers,
Lost Island Project is Back!
in these 10 days we have travelled along Europe to learn more about what we could do in our research. We are ready to Rock the Bank Graham!
Stay with us!
Enjoy!

Read More »

Coral Mystery pt.V the Study

We have one incontrovertible truth: in 13 seasons of fishing, from 1875 to 1886, 14 million kilos of coral were torn from the sea. Yes, you heard right: fourteen million kilos!
We know something else: this coral was different from all others, of an inferior quality, so writes in his report to the Minister, Commander Accini of the frigate ‘L’Esploratore’ who had “directed traffic” around the bank in 1875 and Commander La Via, who sent the Minister a detailed report on the fishing around the bank discovered in 1878. Commander La Via also writes of the quality of the coral, saying:
“The coral harvested on this bank is a common red coral and of a rather inferior quality, both because of the thinness of the branches and that fact that it is blackened in various points, what the fishermen call burnt, attributing the fact to the vicinity of volcanic soil. However, the inferior quality is compensated by the quantity, which greatly exceeds the amount harvested along the coast of Africa and elsewhere.”
There are other important elements: the quality was inferior to the coral fished elsewhere, the coral was blackened because it was near volcanic areas, the quantity harvested was much greater than a boat could normally succeed in finding off the coasts of Africa or elsewhere. So what coral was this?
Prof. Giovanni Canestrini comes to our aid. On 16 August 1882 he sends this report to the Minister “On the researches carried out around the coral banks in the seas off Sciacca.”
Concerning the first bank, the one discovered by Alberto Maniscalco in May 1875, Canestrini says that “it is covered in mud and not very extensive, as it is only 200 meters long and even less in width.” He adds another interesting note for our purposes:
“The coral fished in this site, along with other sea life and a great amount of mud, all lack a ‘sarcosoma’ (a sort of a second skin), indicating that it was dead and thus unable to repopulate the bank.”
to be Continued...
[text taken with license from the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt.IV the Study

Looking at it from the outside, objectively and with no emotional involvement (exactly the opposite of my own reactions), it becomes immediately obvious that many rushed to grab the coral, to plunder indiscriminately, but few, very few, ever asked themselves why this coral was there, in such great quantities, how it ended up there, and so on.
As is my habit, I applied to these studies the methods I was taught by my much beloved professor of Archaeology at the University, when he said:
“Look around you, try to imagine how things were in the period that interests you, ignore what’s been written by your contemporaries, always look for the source, the clues, the testimony of the era.”
So let’s begin.
To be Continued...

[text taken with license of the Author Giuseppe Rajola from the Book Sciacca Mystery]

Enjoy!

Read More »

Coral Mystery pt.III the History

Almost 130 years have passed from the facts narrated.
What really struck me when I first began to study documents and to investigate the subject was that, wherever I went, wherever I looked, in web sites, papers or books on Sciacca and its coral, written by the Saccensi – as the people of Sciacca like to be called – I could find nothing. If you look on the Internet... nothing. If you go to Sciacca, apart from five or six shops that sell a bit of coral they say is from Sciacca, there’s really not much else.
Memory completely wiped out. Why?
Then I understood.
If we consider Torre del Greco, the Torresi fishermen have been going coral fishing since the 1500s, maybe even before that. Three hundred years later, in 1805, the fortunate insight of the Bourbons encouraged the people of Torre to also begin to craft the coral and, of course, to then sell it. Those who talk about a complete supply chain should know that the so highly disparaged Bourbons implemented a complete and successful supply chain over 200 years ago!
When Alberto Maniscalco discovered the first coral bank off the coast of Sciacca, everybody rushed there. Then they found a second... and a third.
Those fifteen years from 1875 to 1890 were only an episode in the history of Torre del Greco. But for Sciacca it was an epic, its entire history of coral. Not even a good one in the end, nor pleasant to remember, as there were more losers than winners.
The opposite was true for Torre del Greco, as on the plus/minus scale Torre could also count on revenue from the crafting of the coral.
In addition, once they finished fishing on the banks of Sciacca, as far as the Sciacchitani were concerned those unsold cases of coral massed in the depots and depreciated in value became a useless and expensive burden.
Not so in Torre del Greco, where everyone fearlessly held on to (and still holds on to) the coral, knowing that sooner or later they would craft it. And so it was.
And so it still is today. Although there is one additional aspect. It was during those years that the shops of Torre became factories, special skills were developed, production lines and industrial processes created.
In the early nineteen hundreds Torre already had companies (I use this term specifically) that employed hundreds of workers, with just as many doing piece work at home. It was during those years that Torre del Greco truly developed, to become first in its field, acquiring a worldwide monopoly on coral craftsmanship that still holds true today.
But we mustn’t forget that the merit for all this belongs to the coral harvested in Sciacca.
To be Continued....
[text taken with license of the author Giuseppe Rajola from the book Sciacca Mystery]

Enjoy!

Read More »