The World Oyster Society

The President’s Message

“Let the sea live. Let us live with the sea.”

Katsuyoshi MORI, Ph.D.
Founder and President The World Oyster Society

“Let the sea live. Let us live with the sea.” This is one of my own favorite sayings that I prefer to use at lectures and at other meetings. “Let the sea live” includes two meanings: One is not to kill the sea. Ocean environments should be preserved, not destroyed. The other meaning advises us to use the sea appropriately. Through the combination of these two, we can follow a course of supporting a wealth of marine life while maintaining sea environments in good condition to the greatest extent possible. We can accept gifts from the sea with gratitude that we can show by providing measures for artificially improving its production even a little. As a result, human beings can exist and co-exist “to live with the sea”. One who searches for the meaning of life in “living with the sea” will find life with the sea. We human beings, depending heavily on the sea for our food, are obliged to use the ocean, which covers about 75% of Earth’s surface, actively and subjectively to continue to live on Earth. However, the sea is not so generous that it permits unlimited development. As long as human beings harmonize with the nature to survive, “Let the sea live. Let us live with the sea.” should be rephrased correctly as “We are sustained by the sea”. In this sense, such a sense of humility that “we are allowed to use the sea” should be embedded in the education of young people. In this case, the most important task is that educators be free from the development-first doctrine with growth as the overriding principle, which was taught when we were young.

It is considered that human beings selected a new lifestyle of agriculture and stock breeding about 10,000 years ago. Human populations grew steadily thereafter. Later, triggered by the Industrial Revolution, humans departed from a terrestrial life framework. One aspect of this departure is that the ecological system of nature includes a material circulating system that is complete, whereas human economical activity has no such system. Our “affluent” society is based on “effluence” technology.

Various phenomena such as ozone layer destruction, global warming, and acid rain, as well as ocean pollution, which now pose global problems, were created artificially because the technologies that created them put settlement of these resolutions on the shoulders of the natural world. None of us can escape from these global scale abnormal phenomena. The atmosphere and seawater surrounding Earth are continuous. Consideration of that fact directly implies that no place on the entire Earth has been reserved as hallowed ground.

Human society has arrogantly embraced the belief that people are almost entirely free from the environment: that they can conquer environments anywhere and anytime. Nevertheless, it is abundantly clear that when environments change suddenly, even humans, with their adaptive capability, cannot cope with changes. There is no outcome but ruin. One readily apparent fact is that a healthy Earth has environments that still guarantee evolution and adaptation of living things including human beings. More correctly, it indicates an ocean planet. The term ocean planet derives from the fact that no planet exists other than Earth where as much as 75% of its surface area is covered by water. I consider that the real practice of “Let the sea live. Let us live with the sea.” points the course to maintaining this planet Earth as a healthy environment for all.

If we recognize the undeniable fact that primitive life born in the sea evolved into the present appearance of human beings, then it might be considered that a clue to resolving the question of how we should live on Earth can be found in the sea itself. As long as we are living things being kept alive in the linkage with the natural world including the sea, we should know much about the sea and others. This is the most important condition for “Let the sea live. Let us live with the sea.” Conclusively, construction and practice of a “Global-environmentally friendly aquaculture system” is nothing more or less than “Let the sea live. Let us live with the sea.”

(December, 2013)

Infection with the new variant of oyster herpesvirus (OsHV-1 μVar) specific for Crassostrea gigas: Its global expansion from France

In the past, several reports have described oyster herpesvirus infections in the American oyster (Crassostrea virginica), the European flat oyster (Ostrea edulis), the Angasi oyster (O. angasi), and the Manila clam (Ruditapes philippinarum).

Consequently, such infections have not always remained limited to Japanese oysters (C. gigas) cultured in France. In fact, oyster herpesvirus has arisen as an important current topic in oyster research and industry circles because this virus is suspected as an agent causing high mortality of C. gigas larvae and 3-12 month juveniles cultured in different locations in France during each summer since 1991. This virus has been designated as oyster herpesvirus-1 (OsHV-1), but it might be said that there has been no positive recognition that this virus is the main causative agent of the C. gigas mass mortality observed in France.

During the summer of 2008, high mortalities of 40-100%, primarily affecting spat and juveniles (12-18 mo old), were observed in all major C. gigas culture areas of France, except in one area at Arcachon in the southwest. According to France’s main marine research institute, Ifremer, the oysters were particularly well fed and spent a lot of energy developing their sexual organs to the detriment of their natural reserves, leaving them vulnerable to OsHV-1. However, scientists do not know why Arcachon oysters have been spared exceptionally.

Regarding the “Summer mortality” in 2008 mentioned above, which shook the French oyster industry, Ifremer scientists characterized the presence of a genotype of OsHV-1 that was not already reported. They designated it as OsHV-1 μVar. This new genomic variant was detected only in C. gigas and was identified as a most probable cause of the summer mortality, suggesting that its virulence is specific for C. gigas. The current outbreak of C. gigas mortality was initially limited to France. However, this species began dying in Ireland in 2009 and in England in 2010. All affected areas had received oyster seed from France. In fact, OsHV-1 μVar was identified in at least in 40% of collected spat batches in 2008 and in 100% of samples in 2009. Ultimately, the culture of C. gigas in France received a crushing blow in 2010.

At least the infection’s expansion to England might have been avoided at least if the research result of Ifremer had been used effectively. Unfortunately, it was not avoided. It is said that the trial of tightening controls over the imports of oyster seed by England was not carried out because of the strong protest of France that such a trial constituted unfair interference in legal business transactions between these two countries. It is arrogance to make a profit simply at the expense of another country. The headquarters of the World Organization for Animal Health (OIE) is located in Paris; nevertheless, OsHV-1 μVar has not been listed as a mollusc disease by OIE, meaning that it is not an issue of concern in the oyster trade. The international trade of oysters infected with it would be prevented if the name of this virulent virus were on the OIE list.

A more severe problem is that the OsHV-1 μVar infection associated with C. gigas summer mortality has now spread throughout Europe to the Southern Hemisphere. This new variant was detected in moribund oysters collected from the North Island, New Zealand during November-December (early summer) 2010, and what is worse, also from Southeast, Australia in January (mid-summer) 2011. For the present, affected areas are localized. However, it is noteworthy that the oyster mortality rate is very high and that the damage extends to C. gigas of market size as well as juveniles. Marketable oysters produced in Australia are widely exported to Asia. Many live and fresh C. gigas imported from Australia arrive at oyster bars and restaurants in various parts of Japan. Until they are brought into these places after their importation, they are often stocked in tanks at the seaside. What do these facts suggest? The probable expansion of OsHV-1 μVar.

The C. gigas that are threatened at present are descendants of oyster seeds exported from Miyagi Prefecture, Japan to France in large quantities. Therefore, brand-new research themes have been presented for oyster researchers. One such theme is related to the susceptibility of C. gigas that are currently cultured in Japan to OsHV-1 μVar, which has emerged in France, where its original seed was first transplanted from Japan.

To protect the oyster industry in Japan from devastating mortality caused by OsHV-1 μVar necessitates preventive measures against its invasion into Japan. I strongly urge and expect that the responsible authorities such as the Fisheries Agency of Japan will begin to take necessary actions to stop its invasion as soon as possible.

(February, 2011)

International Environmental Conservation Activity Based on “Warnings from the Earth” Given through Edible Oysters (Proposal)

The earth is maintained with environmental conditions that allow reproduction of life through birth, and through continuous development, evolution, and diversification. Those conditions are the most important feature of our Earth, distinguishing it from all other planets. The number of species that have ever existed on the earth is estimated as approximately 500 million. The number of the species of organisms that presently exist is presumed to be approximately 15 million. Accordingly, presently existent species are only approximately 3% of the total number of species that have emerged on the earth up to the present. The salient implication is that almost all species on earth have become extinct, and that the present species signify the few winners that have been able to survive throughout their long evolutionary history. Consequently, the organisms that we encounter on the earth at present are valuable global assets: they are objects to be protected with utmost care. Nevertheless, humankind cannot help but use these organisms as food to support life. Considering that the origin of their evolution is the same as that of human beings, that situation is natural.

If the earth were environmentally healthy, reproduction, evolution, adaptation and other important processes which constitute the basic properties of all existing organisms would remain secure. Humans, however, despite their appearance only millions of years ago, and especially since the Industrial Revolution, have moved beyond the limits of an earth-based existence and have plundered nature, including edible organisms, on a global scale without any consideration, thereby destroying earth’s healthy systems. Continuation of the situation will render the ecosystem globally unstable at some future date. Consequently, basic properties and processes of organisms will be endangered, and humans will be smothered out as a result. To prevent that situation, humans should heed the “warnings from the earth” that are given through edible organisms which human beings can contact routinely and observe deeply. Moreover, humans should acquire appropriate wisdom corresponding to those warnings.

To select appropriate edible organisms, it is important to consider the tendencies of their organic evolution, which are roughly divided into improvement and divergence. “Independence” is one general tendency related to that improvement in particular: organisms decrease the degree to which they are influenced by the environment through their evolution, simultaneously, they increase control of their environment. Especially, for organisms with a high level of evolution, the degree of their influence by environmental changes decreases according to the progress of their evolution. Accordingly, few opportunities exist for organisms at a high level to signal environmental deterioration attributable to humans. In other words, when humans use only those organisms that are phylogenetically close relations, humans probably take little notice of the overall deterioration of the global environment. In fact, evolutionarily low-level organisms are more sensitive to environmental changes. They can easily give signals to humans of “warnings from the earth” in their role as suitable edible organisms. Nevertheless, there is a barrier of food preference rooted in traditional food culture. Consequently, it is also necessary to gain knowledge and enlighten the public about building a new food culture that incorporates bioeconomy.

Some organisms are sensitive to small changes of the global environment. We should choose them from among edible organisms, and specify them as internationally indicative organisms. Making full use of advanced biological scientific methods, we should periodically observe sensitivities that are shown by them. The above-mentioned activity is an important challenge for humankind. As conditions in which organisms become candidates for international indicative organisms, the following should be considered naturally. First, relationships between indicative organisms and humankind should be as phylogenetically distant as possible. Second, they must have been used as an important source of protein in all parts of the world from ancient times. Furthermore, they must be cosmopolitan species of industry of the present day. The Japanese or Pacific oyster, Crassostrea gigas exists as one organism that meets those conditions. Furthermore, it is necessary to express biological properties of the internationally indicative organisms in some indexes. Natural bio-defense functions that provide adaptability to the environment can be assessed exactly as a very suitable index.

Regarding the above-mentioned periodical observation, it is effective to initiate a project having international authority and put it into effect. Furthermore, based on results of examination, each country should produce a strategy to rescue the earth through cooperation. We would like to propose an international environmental conservation activity by which this strategy is carried out steadily.

(February, 2010)

The Establishment of the World Oyster Society (WOS)

Nutritive value is high in oysters, so that they are said “milk of the sea”. They are the most traditional seafood for the human. These facts led us to assume that they gave birth to thought of aquaculture and thought of marine environmental protection, meaning that they are the extremely important marine creatures. As an international trade object among marine products, oysters are acquiring greater importance. The first International symposium about oysters was held at last in Tokyo on the 13 and 14 th of July, 2005, under the sponsorship of the Foundation of Oyster Research Institute, Sendai, Japan. It is not too much to say that the above symposium held in Tokyo, that is, The 1 st International Oyster Symposium (IOS-1), was indeed a historically memorable event, because the holding of such an international oyster symposium had been a longtime pending problem for persons concerned with world fisheries. This symposium ended successfully, and, in addition, the later reactions from the inside and outside of our country to it are very good. So, I am satisfied with these results as the sponsor very much. The establishment of the World Oyster Society (WOS) was in one of the important matters decided at the General Discussion of IOS-1. WOS takes a role as the host organization for IOS which will be held in future in many parts of the world, meaning that WOS is placed as the upper organization of the local executive committee which will be set up at a holding place for IOS.

The Steering Committee of WOS consists of 12 members including President who are from Canada, France, Australia, China and Japan as of Jan. 1, 2006. I was appointed President. I will make an effort to fix IOS worldwide as President of WOS.

The vision, mission and objectives, annual dues, steering committee and proceedings are as described later. All of the WOS members are freed from annual dues for the purpose of maintaining a secretariat (The Foundation of Oyster Research Institute, Sendai, Japan) and paying for communications by E-mail. I want that anyone who approves of the vision, mission and objectives will apply for a membership. The secretariat established the exclusive homepage of WOS. By using this homepage together with E-mail, I would like to invite a membership.

(February, 2006)

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