The Romans
John McCabe

The Romans controlled a seemingly endless Mediterranean coastline which furnished enormous seafood treasures. Many different species of fish and shellfish dominated the Roman menu. Oysters in particular were in high demand. It was unthinkable back then to host a grand dinner (or orgy for that matter) without oysters. The Roman emperor Vitellius supposedly gulped down a thousand oysters at one such dinner. There was no question in anybody's mind about the connection between the oyster and the love goddess Venus (the Roman version of the Greek goddess Aphrodite). Oysters were considered the most powerful aphrodisiac available. Additionally, they were thought to give men great prowess on the battlefield. The famous Roman gourmet Marcus Gavius Apicius furnished a number of oyster recipes in his cookbook titled "De re coquinaria" ("About the Art of Cooking"). The book is commonly called "Apicius" in his honor and considered the oldest cookbook in history.

Unlike many other sea creatures, oysters can't hide or swim away when man approaches. They are simply stuck in one spot all their lives, mostly in plain sight on the ocean floor. They could be called "sitting ducks of the ocean." Anybody could simply pick them up in shallow water , take 'em home or to market. And that's exactly what Romans living in the Mediterranean did on a grand scale for a long time. In time oysters became very scarce. Wealthy Romans started posting guards to protect valuable oyster beds. This, however, didn't work for any length of time. During the reign of the Emperor Deocletian (284 - 305 A.D.), one oyster equaled the value of the so called "Denarius", a commonly used Roman silver coin. A laborer could usually earn a denarius by putting in a full day's work.

The Roman conquests of northern European territories also included vast stretches of Atlantic coastline, which were richly populated with the same oyster species as the one back home in the Mediterranean region, the European oyster (Ostrea edulis). Although the Mediterranean Sea does have tides, they are of very low amplitude. It's measured in centimeters or inches compared to meters or feet along the European Atlantic coast. The Romans were thus delighted to see how easy it was to gather vast quantities of oysters on the huge exposed tide-flats of the Atlantic during low tide. Brittany in particular produced copious quantities of oysters which in turn were not only transported to Roman cities and outposts in northern Europe, but also packed in snow and tediously carted across the Alps back to Rome. One can imagine just how "fresh" these oysters must have been upon arrival after such a long trip. Considering the highly perishable nature of seafood in general, most of them had likely already died along the way. The gourmets in Rome who delighted in the consumption of the surviving "northern oysters" surely also had to bring a bit of courage to the table.

The shortage of oysters in local Mediterranean waters and the transportation difficulties of these highly perishable critters over great distances fueled Mediterranean oyster cultivation efforts. The ancient methods implemented were remarkably similar to the "modern" cultivation methods of the 19th, 20th and 21st century. Young European Oysters were collected on natural oyster beds in the Adriatic Sea and transplanted into more accessible saline lakes such as Lake Lucrine near Naples. The practice of transplanting young oysters from areas where oysters naturally reproduce into areas were they don't, yet continue to grow nicely, is still practiced today in Europe on a large scale with the Pacific oyster (Crassostrea gigas). The French Bay of Arcachon, for example, ships enormous quantities of oyster babies aged up to about a year old to oyster growers all over northern Europe, where the young oysters continue to grow very nicely, yet don't reproduce well because of cool water temperatures. Up until the 70s of the 20th century, the production of Pacific Oysters along the US and Canadian west coast was still being supported by imported oyster babies from Japan.

The illustrious Roman writer, Pliny the Elder (Caius Plinius Secundus; 23-79), tells in his book Historia Naturalis (Natural History) of a resourceful and enterprising man by the name of Gaius Sergius Orata. In 95 B.C. Sergius Orata successfully established a large oyster cultivation area at Lake Lucrine near the ancient resort area of Baiae (nowadays called Baia) and the port city of Puteoli (known today as the port city of Pozzuoli). This lake was connected to the Gulf of Puteoli. Most of the vast area occupied by Lake Lucrine in ancient times is now taken up by a mountain called "Monte Nuovo" (New Mountain). The mountain was created by tremendous volcanic activity in 1538. All that is left today of Lake Lucrine is but a tiny body of saltwater the natives there like to refer to as "mariciello" ("little sea").

Orata's oysters were soon in high demand and very expensive! They had a funny name: calliblephara (oysters with beautiful eye lashes). The "eye lashes" referred to the distinctly purple "veining" along the mantle edge of his oysters. Orata's oysters were considered the finest ever. The wise Orata was essentially already practicing what the French oyster growers today call affinage. It is the final refinement of an oyster in both its look and taste by transplanting it into most favorable waters. His chosen Lake Lucrine was no ordinary saline lake. The region is highly volcanic and thermal springs did not only delight wealthy bathing Romans in this resort area, but also constantly fed Lake Lucrine. This fresh water supplement, rich in minerals, had a profound effect on the taste of the constantly filtering oysters - it imparted a special taste which no oyster from the Adriatic Sea (or the Atlantic, for that matter) could ever match. Since the lake was also connected to the sea, Orata's operation had excellent entry and egress for regular oyster shipments. Sergius Orata's oysters ultimately became renowned and were at times considered worth their weight in gold. Soon he became a very wealthy man. However, just like any oyster grower anywhere today, he too had more than his fair share of work and problems. He consequently spent lots of time and money trying to come up with more effective cultivation techniques.

Bath Time for Oysters
One serious cultivation problem Sergius Orata had were the occasional cold winters, which would kill all of his precious oysters in the fairly shallow lake in no time flat. In order to counteract this problem, Orata started building a large suspended water basin supported by posts. Next to this basin he built a large fireplace (a so called praeferium). From the fireplace he then routed ducts under the basin. The heated air in the ducts in turn heated the basin floor and warmed the water sufficiently to prevent the freezing death of his "winter oysters." His idea worked out well and he proceeded to built several more of these heated oyster basins. Inadvertently he had also invented the principle of heated floors. After Sergius Orata's death, Roman architects showed much interest in his invention. As it turned out, Orata's "warm oyster baths" also functioned very nicely as "warm people baths." Soon, "suspended bathing rooms" (called balneae pensiles) started springing up in the Roman Empire. Unlike the crowded bath houses dependent on thermal springs, these warm baths could be built just about anywhere. Additionally, the floors and walls of homes could now be heated by ducted hot air, steam or smoke. This ancient central heating system is referred to as a hypocaust (hypocaustum). It was particularly well received by Romans stationed in the cold parts of northern Europe. They soon started installing double floors in their homes and vented the hot air via tile flues in the walls. In the German city of Trier (during Roman times called Augusta Treverorum) one can still view the remnants of this type of Roman architecture.

Warmed "oyster baths" are still being used by some oyster growers in northern Europe. A prominent German oyster grower, Dittmeyer Austern, who operates along the vast tide flats of the cool North Sea (on an Island called Sylt), maintains large inside basins to protect his stock. In the winter time, the grower transfers his oysters from the tide flats into these warm basins fed by ocean water.

Hang it up
Rare 3rd century A.D. Roman souvenir flasks from the area of Baiae or Puteoli (nine of these flasks are known to still exist) reveal additional clues to the cultivation techniques employed by ancient Roman oyster growers. The flasks depict a series of buildings. One particular building built on pylons is marked as ostriaria. A rope hanging from this building suspends a round ball between the pylons. The "ball" is undoubtedly some kind of net or mesh sack full of oysters, which could easily be lowered into the water below. While hanging in the water above the sea floor, the oysters were safe from predators as well as contamination by mud and silting. Undisturbed, the oysters could simply go on about their business of constantly filtering the surrounding lake water. The oyster sacks could conveniently be pulled from the water for cleaning, sorting, arranging, or filling an order for fresh oysters. They could be transported easily to the aforementioned "oyster baths" in the event of a harsh winter. Tasty and squeaky clean oysters were likely produced en masse in this way by Sergius Orata and later oyster growers in this region. The filling of mesh sacks with oysters and hanging them from rafts or posts above the sea floor is still a popular method of oyster cultivation today.