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California Caviar

Caviar goes green, as eggs from farmed domestic sturgeon now rival the best russian roe

Juliane Poirier Locke

As beluga sturgeon numbers drop, farmed white sturgeon and other North American fish such as salmon and paddlefish offer tasty and environmentally sustainable alternatives.

Courtesy Caviar Emptor

In the damp and cavernous warehouse, conversation drowns in the echo of splashing. In the rows of concrete pools, each 40 feet square and 10 feet deep, roiling water marks the presence of tens of thousands of fish barely discernable in the dim light. At a pool nearest the roll-up door, the light from an overcast day penetrates the clear water and illuminates a pool filled with sturgeon.

Sturgeon have been swimming the rivers and seas of the northern hemisphere largely unchanged since the reign of the dinosaur over 200 million years ago. But today, these nearsighted bottom feeders face an uncertain future, not merely from the ubiquitous water pollution and habitat loss, but also from a curious form of human gluttony.

While all 27 sturgeon species are in some degree of trouble, a few are being fished aggressively toward extinction because their eggs go so well with salt and a champagne chaser. Sturgeon roe makes the world’s most coveted caviar.

Those who crave caviar seem above all to want their fish eggs delivered from the Caspian Sea, where 90 percent of the world’s caviar supply originates and where the beluga sturgeon is dangerously near extinction. Those working to protect sturgeon are demanding bans on Caspian caviar imports, particularly to countries with the biggest appetite and pocketbook for caviar: the United States, Japan, the European Union, and Switzerland. But, at the same time, sturgeon advocates are pushing another means of helping preserve wild sturgeon populations—caviar produced from aquaculture, exquisite enough to satisfy connoisseurs.

Such caviar may originate in the female white sturgeon (Acipenser transmontanus) now swimming at my feet. Indigenous to the west coast of North America, these sturgeon are at least five feet long, with belly sections thick as a runner’s thigh. Their gray-skinned bodies move through the water with muscular flicks of shark-like tails, a motion made supple by spinal cartilage. Five rows of bony plates serve as body armor.

A few blunt snouts rise to the surface of the pool, trailing whiskers, or barbels, that “taste” the presence of food; the sturgeon relies much more on its sense of taste than on its inferior eyesight. The primitive eating tube, which emerges as needed from an ungainly position deep in the fish’s chin, makes an ugly mouth but an excellent vacuum. When not in use, the tube retracts.

The very tiny teeth that juvenile sturgeon use for scraping food from rocks are only temporary tools. Over time a sturgeon will grow to depend wholly on inhalation to procure food, sucking in all the mollusks, fish eggs, crayfish, worms, and other small fare it can swallow; when large enough, it will also devour the likes of anchovies and post-spawning salmon that drift dead along river bottoms.

The wholly toothless adult, although it cannot bite or chew, scavenges with abandon. Supported by a remarkably hearty digestive system, sturgeon have been known to dine on disintegrating ducks, baby seals, drowned cats, and even tin cans.

Left to their own devices, sturgeon will eat their way toward whale-like proportions. In fact, the beluga sturgeon dwarfs all other freshwater fish species on the planet. Centuries ago in eastern Europe, someone fished up a beluga 28 feet long and weighing close to 4,600 pounds. In the same era, an enormous, ripe female beluga was caught; her roe alone weighed 900 pounds.

White sturgeon run a close second in size to the beluga. Giants of the species found on this continent include a 20-foot specimen from the Fraser River in Canada, caught in 1912 and weighing 1,800 pounds, and a 1,500-pounder pulled from the Snake River as recently as 1928.

When Stafford Lake reservoir in Novato, California, was partially drained for dam repairs in 1985, the legendary “monster” long said to have haunted the waters was revealed to be a 170 pound white sturgeon about 65 years old and 7 feet long. It was captured live but did not, however, survive relocation to the Academy’s Steinhart Aquarium in San Francisco. One legend even claims Scotland’s famed Loch Ness monster is a dirigible-sized sturgeon.

But sturgeon this size are mere fish tales now. Thanks to poaching and habitat destruction, the time of truly massive sturgeon is over.
Smaller ones still swimming in the wild are routinely killed while still in their teens, barely old enough to reproduce. And reproduction is nothing a sturgeon rushes into. Females in the wild spawn for the first time between the ages of 15 and 25 years of age, depending on the individual and habitat conditions. Unlike salmon, sturgeon females can breed several times over a lifespan.

Females, which produce on average between 300,000 and 4 million eggs to insure survival of one sturgeon, may spawn only once every 2 to 8 years. If they become excessively stressed, females will simply absorb their eggs until their next spawning cycle. Since sturgeon are said to live between 80 and 100 years, fully restoring a sturgeon population would take at least a century.

Over the last five years, poaching has cut the sturgeon population in San Francisco Bay and Delta in half. Poachers may try to catch spawning females but more often go up and down the river trying to buy ripe female sturgeon from fishermen. A few years ago, the U.S. Fish and Wildlife Service helped the state Department of Fish and Game break up a large caviar poaching ring operating in the Delta; they made around 20 arrests and seized $12,000 worth of caviar.

Aside from the threat of arrest, poachers have little incentive to stop killing sturgeon. Ten pounds of roe sells on the black market for $1,000. According to Inga Saffron, author of Caviar: the Strange and Uncertain Future of the World’s Most Coveted Delicacy, for every pound of sturgeon eggs fished up legitimately for the worldwide caviar market, ten pounds of illegal eggs are sold.

The snob appeal of Caspian caviar is a formidable obstacle to those trying to preserve wild sturgeon. Nevertheless, more and more people are becoming converts to the domestically farmed caviar of western Europe, China, and the United States.

The most consistently admired domestic caviar is Sterling, the brand of caviar made here at Stolt Sea Farm in Elverta, California, just north of Sacramento. These sturgeon are bred from domestic stock; the original brood stock came from the Sacramento River. With no river in sight, this remote acreage seems a rather dry spot for a fish farm; however, well water is plentiful here and emerges at a consistent 70 degrees. “A hundred miles north or south would have different well water,” explained Peter Struffenegger, who manages the farm. “It’s the warm water that allows sturgeon to grow year-round, which doesn’t happen in the wild because of seasonal water temperature fluctuations.”

The reliably warm water isn’t just good for the fish, but keeps tank heating bills down as well. The venture has proved costly enough; it took eleven years of fish tending before the first tins of caviar hit the market.

Yet in the nine years since then, this upstart caviar has done well.

From a mere 50 pounds of caviar in their first year, Stolt, by far the largest producer in the States, last year sold caviar in the tons. The fact that the swanky Manhattan gourmet store Zabar’s carries Sterling should be endorsement enough, yet it has also been praised in food reviews from the Wine Spectator to Seafood International. Restaurants in San Francisco and New York keep it on the menu, some to the exclusion of Caspian imports. Other related species are being farmed for their roe in other U.S. states, but it is California-grown caviar that has fared particularly well in blind tastings. Still, some people continue to refuse anything without a Russian label. Shady caviar dealers exploit this bias, and many a snob has been unwittingly deceived.

Under the Soviet Union, the Caspian caviar trade was tightly regulated. But since the fall of the Iron Curtain in 1991, overfishing and illegal caviar production has skyrocketed. In this corrupt market, many a connoisseur paid for beluga and received lesser roe. For example, paddlefish caviar—possessing a less complex flavor than sturgeon caviar—was labeled as beluga and sold by the ton to airlines and cruise ships. No one seemed to notice the difference. Caviar shipments to the U.S. are now genetically analyzed to verify authenticity.

Even when the stuff labeled beluga is the real thing, it can come with unwanted extras. Some Caspian poachers make caviar outofdoors under filthy conditions, or rinse it in Volga River water contaminated with high levels of bacteria, viruses, and industrial chemicals.

While black market caviar production standards are questionable, the preservation and transport standards are even lower. Salt is the traditional ingredient used to preserve the eggs, but caviar is routinely adulterated with less savory additives. For example, Saffron writes that some countries, including Russia, Kazakhstan, Turkmenistan, and Iran, preserve and sweeten caviar with borax—a household roach killer. The use of borax is illegal in U.S. caviar production. Caviar shipments smuggled into this country in suitcases have traveled for an unknown length of time and without the benefit of refrigeration.

It’s more than a little chilly in the processing rooms at Stolt. Before entering the metal building, I dip the soles of my shoes in a small tub of disinfectant. Inside the temperature drops to 40 ºF and I shiver while donning the requisite hairnet and wrap-around lab apron. Thus clad I stand in a hall where fresh sturgeon meat is being packed in an iced shipping container. Through vertical slats of plastic hanging in the “kitchen” doorway, I can see the caviar masters at work.

The room’s white sinks, counters, walls and aprons all conspire to draw the eye toward the glistening mass of tiny green-black spheres cradled in the gloved hands of a worker. The roe is brought to this frigid room seconds after it is cut from the fish. It is rinsed and gently pressed by hand through a sieve to separate the eggs from each other. It is critical not to bruise the eggs in the process. The eggs are rinsed, drained, and lightly salted, a method known as malossol. A 100 pound sturgeon produces about 10 pounds of caviar, each egg about 1/8” in diameter.

Caviar masters distinguish the quality of sturgeon roe by sight and bite. The eggs must be firm, attractive and tasty. There should not be a fishy quality to the taste, but a complex, subtle flavor suggestive of the ocean. Color, too, is a big deal to caviar eaters. Roe that fails the test is discarded. The rest is gently placed by hand into tins stored at 22-24 ºF, safely above its freezing temperature. There it will age for at least three months, which will enhance its buttery flavor. The flavor of Sterling caviar compares closely with osetra caviar, from the Russian sturgeon.

While there is some hope of breeding sturgeon to select for superior caviar characteristics such as firmness, egg size, color and taste, preliminary studies by researchers at UC Davis haven’t been too promising. “We only sampled a few hundred fish,” explained Jeff Rodzen, geneticist at UC Davis and Department of Fish and Game who completed the three-year study in 2001. “But there appear to be no heritable traits other than size.”
Studing the genetics of sturgeon is made extra tricky by the unusual genome of this fish’s ancient lineage. “Humans have chromosomes in two copies,” explained Rodzen, “While white sturgeon carry eight copies, and other sturgeon species carry twelve copies.” The genetic complexity of sturgeon is a big reason why there is still not a blood test that can determine a sturgeon’s sex.

As a result, Stolt relies on a surgical incision to distinguish males from females. While still juveniles, males are removed to a holding tank where they will fill restaurant orders for sturgeon meat. At present, farmed sturgeon offers an advantage over wild-caught Delta fish that retain high levels of mercury in their flesh.

Most females are put back in their pools for another five to seven years, until they are ready to produce their first batch of roe. Afterwards the brood fish are returned to the water until they are prime for harvesting again in another two to eight years.
Down on the farm, the pampered females are carefully observed. Meals are

fishmeal pellets strewn by robotic arm over pools that cover five square acres. Likely due to the consistently warm water, a steady nutritious diet and relative lack of stress, the female sturgeon at Stolt become ripe—ready to spawn—without artificial inducement anywhere between eight and ten years of age. After their roe have been removed, females are also sold for their meat.

In a small tasting room across from the caviar production room, I am handed a tiny plastic spoon and invited to partake of the salted orbs. Caviar must never be eaten with a metal spoon, and tradition calls for mother-of-pearl, but plastic works very well. I dig in. As I roll the eggs around on my tongue then savor the small pops of resistance the firm roe make against my teeth, I am pleased. It tastes like mild, salted seafood with a novel texture. Food critics call the flavor “rich and buttery,” though neither comparison comes to mind for me. I do wonder how much of my enjoyment is determined by taste and how much by myth.

Before legend sang the praises of caviar, people often found the slippery dark masses of salted fish egg entirely disagreeable. King Louis XV of France received a gift of the very finest caviar sent by emissary from Peter the Great. At first bite he spat the stuff on the palace floor in disgust. For many years caviar was a throwaway food, pressed into loaves and eaten by the lower-class poor or given away at liquor establishments to increase thirst. American settlers threw sturgeon roe to pigs. It would take time and imagination to transform pig slops into elitist fare.

Today, eating a spoonful of wild-caught caviar is like wearing an endangered fur. According to Vikki Spruill, president of the international ocean conservation group SeaWeb, eating beluga is in fact the height of rudeness. "It’s absolutely in bad taste, says Spruill, "to eat the eggs of a fish that is in such dire straits."

For those who don’t care about saving the last beluga, aquaculture at leastoffers an untainted food product. “One thing we have that the Caspian Sea doesn’t,” boasts Struffenegger, “is a very consistent product.” Certainly the conditions under which it is made are comparatively consistent and clean; for half the price, California aquaculture offers an alterative to black market deceptions, borax preservatives and mushy roe tainted with dirty Volga River water.

Beleaguered Beluga

The Caspian sea is the largest landlocked body of water on Earth and the very womb of world caviar production. It is also the last stronghold of the beluga sturgeon, now being fished to extinction for the global caviar trade.

Fed by more than 100 rivers, the Caspian is ringed by Russia, Kazakhstan, Turkmenistan, Iran and Azerbaijan. All are in conflict over how to manage what Caspian sturgeon still remain.

The only places where Caspian sturgeon still spawn naturally are in waters off Iran and Kazakhstan. Beluga populations are largely stable in Iran and still numerous in Kazakhstan, but cannot be safe from the degradation of the Caspian itself.

The water here isn't what it used to be. The mighty Volga River flows into the northwestern corner of the Caspian, providing 80 percent of its total water volume and 75 percent of its sturgeon. Once upon a time, the Volgas's spawning grounds and nutrient-rich waters were plentiful and ideal for sturgeon. But starting in 1959, hydroelectric dams cut off sturgeon access to the Volga and diminished the amount of nutrients flowing into the Caspian. Now hatcheries ensure sturgeon reproduction, but the nutrient-poor water may have decimated the species upon which sturgeon depend for food.

Industrial pollution has further decreased the odds of sturgeon survival. Wastes from nearby oil fields film large areas of the water's surface, preventing oxygen transfer and suffocating sturgeon and other fish. The problem is particularly acute off the coast of Azerbaijan, where sturgeon overwinter in the warmer waters. More oilfields are planned for the eastern coastline of Kazakhstan, another shallow spot favored by sturgeon during winter.

But overfishing poses the biggest threat to sturgeon survival. Sadly, the decline of the beluga, and its increasing rarity, has only made the hunt more lucrative.

Fishermen who used to catch 50 beluga in three hours are now lucky to catch one in a day. About 90 percent of the historic beluga population has disappeared in the last 20 years and, according to SeaWeb, almost half of that decline has occurred within the last two years. It is generally thought that beluga no longer spawn under natural conditions but rely entirely upon hatcheriies for reproduction.

The Committee on International Trade in Endangered Species (CITES), which monitors trafficking in rare plants and animals, began limiting caviar exports in 1998.

But the United States remains a major culprit in the beluga's downfall. About 130,000 pounds of beluga caviar is eaten here annually-roughly 60 percent of the world supply. Earlier this year, the United States Fish and Wildlife Service placed beluga on its list of threatened species. The United States is expected to prohibit most beluga caviar imports from the Caspian Sea by 2005. Those making (controversial) efforts to farm non-native beluga in Florida want exceptions ot the ban. So do fans of Iranian caviar, since Iran operates the most sustainable Caspian fishery.


Julianne Poirier Locke is a journalist and author. She lives at the foot of Mount St. Helena, in California.