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Part One -- The Invention of Caviar
1 How to Catch a Sturgeon
The Khazars believe that deep in the inky blackness of the Caspian Sea there is an eyeless fish that, like a clock, marks the only correct time in the universe.
--Milorad Pavic, Dictionary of the Khazars
According to all the usual rules of evolution, the sturgeon should be extinct already.
Sturgeon are in no hurry to reproduce. They take almost as long as a human being to reach sexual maturity. While a single fish may carry millions of eggs in its belly, the odds are that only a single hatchling will survive into adulthood. That lone offspring will then have to risk its life to reproduce. Swimming upriver along the same course its parents took, the young sturgeon will ramble leisurely through narrow channels where even the least enterprising of its human predators can easily pluck it from the water.
It was not always this way. The sturgeon had already been making its way up the earth's rivers for 250 million years when human beings first appeared. Sturgeon are older than the dinosaurs. They were already ancient when such bony fish as the perch, cod, and striped bass began to appear. Yet, even as the earth cooled, dinosaurs veered into extinction, and mammals came to dominate the land, the dogged sturgeon somehow kept plodding along. It remains a big, slow-moving beast, sweetly curious about the goings-on above its head and lumpenly passive when it runs into danger. Scientists call the fish a living fossil because the sturgeon have changed little over the millennia. A sturgeon caught today could fit more or less neatly into a petrified impression left by its Jurassic counterpart.
Today sturgeon live exclusively in the waters of the Northern Hemisphere. Most sturgeon are anadromous, which means they make their homes in the sea and commute to rivers to spawn. They are usually most comfortable someplace between the two, in the brackish deltas and tidal estuaries where salt water and fresh water collide. These mildly saline border zones nourish immense numbers of small creatures such as worms and crayfish, which keep the bottom-feeding sturgeon well fed. The Caspian's fame as the ideal home for sturgeon is due to the fact that it is more of a salty lake than a real sea. The northern portion of the Caspian, where the Volga spills into the sea, is unusually shallow and warm, and contains the highest concentration of sturgeon in the world.
The sturgeon still looks like an animal that might have cavorted with the dinosaurs. Young sturgeon have a puppy-like cuteness, as well as a curious nature, but with age their features grow more jowly, bloated, and monstrous in size. Perhaps as compensation for its passive nature, the sturgeon's grayish tree trunk of a body is sheathed in a protective bony mantle. Five rows of hard plates, or scutes, run along its sides and spine like ranges of tiny mountains, each peak rising to a point sharp enough to inflict a painful wound on less hard-bodied creatures. To complete their menacing image, sturgeon have big sharklike tails that can deliver a powerful blow.
It is the sturgeon's huge sloping head that seems to mark it as a holdover of another time. The head is out of all proportion to the rest of its body. When viewed from the top or sides, the sturgeon's snout may look no more unusual than a shark's head. But the sturgeon has no powerful jaws to open, no dagger teeth with which to rip its food to shreds. The sturgeon's mouth is tucked far under its chin, close to its belly, and there is not a single tooth inside. Skimming over the sea floor, the sturgeon extends its soft blubbery lips like a hose to vacuum up larvae and mollusks embedded in the silt. Four fat whiskers under its chin act as sensors to identify the choice morsels. Without them, this half-blind, ancient creature would hardly know what its toothless mouth was up to.
Despite its antiquated, tubular mouth, the sturgeon is a machine designed for eating. The word sturgeon comes from the German verb stsrer, which means "to root." After nosing around up to its eyeballs in the mud, the sturgeon uses its powerful tail to swoosh the food toward its mouth. It swallows everything whole, even clams in their shells. Sturgeon are opportunistic feeders, happy to stray from their standard diet when something interesting comes along. The bigger sturgeon, such as the beluga, will sometimes go after herring, ducks, even baby seals, while the Pacific Ocean's white sturgeon routinely dines on dead salmon that float downriver after spawning. Sometimes after a frenzy of feeding, the sturgeon will leap joyfully out of the water, like a shimmering phantom from the deep, frightening the life out of fishermen in small boats.
So far, scientists have identified twenty-seven species of sturgeon in the Acipenser order. The number is a subject of dispute because scientists are always arguing over what actually constitutes a distinct sturgeon species. The fish that produces osetra caviar, for instance, is called the Russian sturgeon by the Russians and the Persian sturgeon by the Iranians, but scientists now suspect they are the same species, Acipenser gueldenstaedtii. The gueldenstaedtii also shows up in the Black Sea, off the coasts of Romania and Ukraine. The Romanians call it nisetru, while it's just plain Russian sturgeon to the Ukrainians. The two other sturgeon species famed for their caviar, the beluga and the stellate, the mother of sevruga, also happen to be found in both the Caspian and Black Seas.
Many people think a sturgeon is just a sturgeon, but the twenty-seven varieties vary enormously in appearance and size. The beluga, or Huso huso, can easily weigh a ton, making it the largest freshwater fish on earth. As it ages, it takes on the aerodynamic proportions of a blimp. Its elongated snout becomes rounder and less pronounced. At the opposite extreme is the svelte sterlet, the Acipenser ruthenus, which rarely weighs more than twelve pounds. The sterlet is the only Russian sturgeon that does not venture into the sea. Celebrated for its flesh rather than its eggs, the yard-long fish is still caught in the rivers of Eastern Europe, central Russia, and Siberia.
Because the sturgeon always returns to the same place to spawn, certain species are found only in a single river basin. The Adriatic sturgeon exists only in the Adriatic along the coasts of Italy, Greece, and Albania. The few remaining specimens of the common European sturgeon inhabit the Mediterranean regions of France and Spain. The Atlantic sturgeon is native to the East Coast of the United States. The Pacific white sturgeon, which nearly rivals the beluga in size, spends all its time in the waters of California, Washington, and British Columbia, trying to satisfy its voracious appetite.
The sturgeon's constant eating makes for a big fish. Since sturgeon never really stop growing, the older ones tend to be immense. The beluga, which may live more than a century, will swell in girth until it is as big around as a man's hug and twice as long as a pickup truck. The largest beluga on record weighed 4,570 pounds and stretched twenty-eight feet. Caught in 1736, it was an empty, presumably male. But some thirty years later, Cossacks on the Ural River recorded a female beluga weighing a mere 2,520 pounds. She reportedly yielded an impressive nine hundred pounds of roe, which would have made her worth half a million dollars at today's prices.
North American varieties of sturgeon can also attain similar gargantuan proportions. A Pacific white sturgeon, the Acipenser transmontanus, pulled from the Fraser River near Vancouver in the 1890s tipped the scale at 1,600 pounds, and measured eighteen feet from nose to tail, longer than the dinghy the fishermen used to catch it. The averages are even more impressive than the extremes: in the 1860s, the typical white sturgeon weighed 500 pounds. Such giants would be inconceivable today because few sturgeon are allowed to live long enough to amass such bulk.
No matter what its size, a good deal of a sturgeon's poundage is devoted to reproduction. A female's eggs can account for 15 percent of her body weight. It is not unusual for one female to carry around 10 million eggs. The bigger the mother sturgeon, the bigger the individual eggs. The three giants of the sturgeon family--the beluga, the kaluga, and the white sturgeon--produce dark gray beads roughly the size of the capital O on this page. The roe of the kaluga, which roams the Amur River between Russia and China, is sometimes passed off as beluga caviar because the two are so similar, although kaluga caviar lacks the brininess of beluga. While the white sturgeon eggs are a little smaller, they have an intense flavor. Size is not everything when it comes to caviar. Large beluga eggs sometimes lack the intense, oceanic zing of more fine-grained varieties. Connoisseurs insist that they prefer pinhead sevruga eggs, which are only half the size of beluga caviar.
Caviar can be made from the roe of any sturgeon except the green sturgeon, a rare species that inhabits the Pacific coast of California. Both its eggs and flesh are said to be poisonous. For much of the twentieth century, only the roe of the beluga, Russian sturgeon, and stellate were considered fit for making caviar. But as the numbers of these sturgeon have dwindled, caviar makers have turned to such scorned varieties as the white sturgeon, the Mississippi shovelnose, the Missouri paddlefish, and the Atlantic Sturgeon.
Sturgeon eggs vary in color, from black to olive green to mustard. Beluga eggs are often grayer than the Russian sturgeon's osetra. The diverse shadings are usually a reflection of what the fish ate and how ripe the eggs were when the fish was caught. A sturgeon taken too early in the spawning cycle, like those caught at sea, will have jet-black eggs, but they will be gooey with fat and won't deliver a satisfying pop when eaten. As the fish gets closer to spawning, its eggs become lighter, tauter, and more flavorful. Fishermen insist that the best caviar comes from fish caught three or four days before spawning. If they catch a sturgeon too early in its migration, they often keep it alive until the eggs are ripe. In the Caspian, where some sturgeon spawn in the spring and others in the fall, caviar made from the spring catch is said to be more flavorful than the production from the fall migration.
For centuries, connoisseurs have been fascinated by the subtle variations in different types of caviar. The rarest and most expensive type is easily identified by its unusual pale, yellowish color. Known as golden caviar, it is the stuff of legend. In tsarist times, golden caviar was so venerated that all specimens were supposed to be delivered to the royal court. Stalin later emulated this practice. Perhaps the rulers saw their own image reflected in the glow of the golden eggs. Scientists now believe that these eggs, if fertilized, would produce albino sturgeon. Despite the high price golden caviar commands, some dealers say that it is actually quite bland, proving that taste is determined as much by the eye as the mouth.
THE STURGEON needs a multitude of eggs because its chances of producing an offspring are incredibly slim. The smallest of the sturgeon do not spawn for the first time until they are more than six years old. But jumbo varieties such as the beluga and kaluga, as well as some northern paddlefish, only reach maturity when they are well into their twenties. Before the days when Caspian poachers scoured the open sea for sturgeon, the juveniles there could at least count on a carefree youth. These days, a sturgeon's life typically ends while it is still a teenager.
When a sturgeon does get a chance to spawn, at least it does not have to concern itself with eating. As it heads upriver, the sturgeon lives mostly off its fat, its mind focused on nature's imperative. Pushing against the current, the sturgeon travels about twenty miles a day for several weeks until it reaches its spawning grounds. Sturgeon are extremely choosy about where they will lay their eggs. The fish's internal wiring demands that it return to the same area, even to the same spot, where it was hatched many years earlier. A stellate born in the Volga River would never consider a trip up the Kura River, although both waterways drain into the Caspian, and both are host to populations of stellates. If a dam blocks the way to a sturgeon's birthplace, it will refuse to spawn. The beluga, for instance, no longer reproduces naturally in the Volga or the Danube because its ancient spawning grounds are dammed.
When the sturgeon finally arrives at the spot where it and all its ancestors were born, the parameters for successful spawning grow even more precise. The sturgeon needs to find a rocky stretch of river to lay her eggs. The water should be shallow, but washed by a strong current.
While fertilization is a highly impersonal affair for most fish, sturgeon do it differently. A nineteenth-century sturgeon expert named John A. Ryder discovered that as the roe sturgeon approaches her spawning place, the male fish will pick up her scent and swim to join her. The males pull up alongside roe fish, pressing their bodies tightly against her abdomen, a behavior that stimulates the female to release her eggs, and the males their fertilizing milt. If the female sturgeon fails to meet a potential mate on the trip upriver, she will rub her belly against the hard rocky surface, and hope a male will come along later to fertilize them. Nowadays, with so few sturgeon around, such serendipity is rare.
Within a day, the fertilized eggs hatch into thousands of frenetic, transparent fish fry. Most will be eaten by bigger fish, including the sturgeon themselves. Pollution and sickness will kill others. Of the survivors, only a handful of fingerlings will have the energy to swim downstream to the sea. Rarely does more than one make it all the way.
Left to themselves, sturgeon might very well continue happily in their inefficient ways. Ovid, who lived near today's Black Sea port of Constanta, called the sturgeon a "pilgrim of the most illustrious waves." Unlike salmon, which die at the end of an exhausting migration, sturgeon live to spawn again. A beluga can produce eggs every seven years; other sturgeon may swell as frequently as every two years. As compensation for its inefficient habits, nature gives a sturgeon as many as ten chances to reproduce over its long life. Since it only needs to generate two adult offspring during its lifetime to keep the population stable, the odds for the next generation are reasonably good as long as the sturgeon keeps traveling upriver every few years.
From the Hardcover edition.