[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
THE CAVIAR CONNECTION
With the help of a Soviet defector, Californians are
breeding fish that lay precious eggs
By Peter Steinhart
National Wildlife:December/January 1986
ELM BORDNER lilts a five-foot, eighty-pound sturgeon out of a holding
tank at the University of California at Davis. In so doing, he may be
raising the beginnings of yet another odd California trend. It is a trend
set in motion by the defection of a Soviet official and nurtured by
changing tastes in food in America. But it depends upon an increasing
understanding of a strange and troubled fish.
The fish is huge, gray and prehistoric looking. It has rows of silvery
bony knobs down its back. Four pink wormlike barbels dangle in front of
its mouth, which is hidden deep under its face. No one would call it
pretty. But the fish, a white sturgeon from the Sacramento River, is a
prodigious egg layer. !t is about to yield to Bordner. a researcher in
the University's aquaculture program, thousands of shiny black eggs. And
that makes it an object of keen interest.
There are at least 20, and perhaps as many as 80, private efforts
underway in California to establish a breeding stock of sturgeon. The
University's program is the first and probably the most advanced. It was
designed to help replenish sturgeon fisheries in state waterways. But
like the other eflbrts, it is also attempting to restore an industry that
once thrived in the Golden State:the production of caviar, one of the
world's two or three most expensive luxury toods.
You find caviar on the menus of most expensive restaurants and on the
sideboards at catered parties and political fund raisers:crisp dark fish
eggs to spread on thin, oven-toasted bread. It is so expensive that it
sells by the ounce, and it is expensive because it is rare.
America produced some 60,000 pounds of sturgeon caviar last year,
primarily from paddlefish caught in Mississippi River tributaries, or
from white sturgeon caught in the Columbia River. Iran produces a similar
amount and China a small quantity. But the lion's share, about 90 percent
of the world's production, comes from the Soviet Union. The heart of the
industry is on the Caspian Sea, where a single Soviet station once
harvested 15,000 sturgeon in a day. One pregnant sturgeon can yield as
much as 40 pounds of roe. In recent years, though, increased pollution
and dams blocking fish migration Russian rivers have reduced sturgeon
numbers and, in the process, the Soviet's caviar harvest.
Today, the Russians export only 20 percent of what they produce. And only
5 percent of that is beluga, taken from the beluga sturgeon, the finest
caviar--a shiny black roe that sells for as much as $800 a pound in this
country. "The good beluga," observes a proprietor of a New York gourmet
shop, "has a certain aftertaste, a little sweetness and elegance, that
makes it special."
Californians have produced and exported caviar before. In 1872,
commercial interests were harvesting as many as 5,000 sturgeon a month
from California waters. But by 1917, overfishing had taken its toll;
state authorities closed the fishery to both sport and commercial
fishermen. The sport fishery reopened in 1954, but by then the caviar
industry was forgotten. There were too few fish to induce commercial
production, and no one knew anything about wild sturgeon. No scientific
research had been conducted in this country on their breeding biology,
explains Robert Rawstron of the California Department of Fish and Game,
because "they are a hard fish to work with." A sturgeon may take 20 years
to mature, and then may live more than 150 years. "By the time you've
seen two generations of fish," says Rawstron, "you're talking about a
scientist's career." So, adds Bordner, "Sturgeon was a resource that
nobody was interested in."
In 1977, however, Sergei Doroshov, a Russian aquaculturist with broad
experience in the Soviet caviar industry, defected. When he came to
California in 1980, he brought with him to the University a knowledge of
the natural history and biology of sturgeon.
Doroshov was attracted to California because of the white sturgeon. It
yields a caviar comparable to Soviet beluga. Says Mats Engstrom, a San
Francisco aquaculturist and wholesaler who is trying to develop his own
domestic sturgeon stock, "The quality is such that it should be equal in
Caviar comes from one of the world's strangest families of fish. There
are 25 different kinds of sturgeon, 8 of which live in North America.
Most are anadromous, living part of their lives in seawater but migrating
to freshwater to spawn. The creatures survived almost unchanged in our
rivers and bays for some 200 million years.
Sturgeon have no bones or teeth. They are all cartilage. Instead of a
backbone, they have a notochord, a flexible cartilaginous rod running
down the back. The asymmetrical tail is also a primitive characteristic,
once seen in ancient fishes that lacked swimbladders to help them float.
Those creatures needed the lift provided by a tail to help them move
through the water.
Some of their other qualities are simply strange. Sturgeon can, for
instance, evert their mouths into funnels to siphon up clams and crabs
from bottom muds. And some species grow to enormous sizes. There reports
of sturgeon caught in European rivers that were 28 feet long and weighed
more than a ton. Even today, eight-foot fish are occasionally taken from
the Sacramento River.
After the Civil War, as the nation developed its own class of
millionaires, it also developed a taste for caviar. Unfortunately, the
growing caviar market put enormous pressure on the sturgeon, and all of
the American species were plundered almost to extinction.
Today, the creatures are still harvested in the Columbia River and in
Mississippi River tributaries, and there are small fisheries for Atlantic
sturgeon in New York and South Carolina. But elsewhere, dams and
pollution have added to the fish's troubles. The shortnosed sturgeon of
the East and the lake sturgeon of the Midwest are both on the federal
Endangered Species List.
The taste for caviar, however, persists and so does a black market trade
in the delicacy. In California, the commercial harvest of sturgeon is
prohibited, but sport fishermen can legally catch the fish, remove the
eggs and sell them. Some people do so far beyond legal limits. In
California, state undercover agents bought more than 600 pounds of
illegal sturgeon meat early in 1985, and they believe that the poachers
may have sold the caviar to restaurants. Says Duane Johnston of the
California Department of Fish and Game, "You can buy 100 pounds of caviar
from a sports fisherman for $100. The processing of it is real cheap. You
can put it up in jars and sell it for $40 an ounce." Since legal meat and
caviar can be brought from Oregon, and since sports fishermen may possess
meat and roe, catching poachers in California is difficult.
Authorities believe the black market trade may be thriving because the
demand for legal caviar is growing so rapidly. Legitimate caviar sales in
the United States rose from 200,000 pounds per year in the late 1970s to
about 700,000 pounds last year. Says Mat Engstrom, whose California
Sunshine, Inc., processes caviar, "Our business is growing more than 100
percent per year. We can't supply enough." Restaurants are the primary
customers. With two-income families, observes Engstrom, couples eat out
more often and their tastes have become more luxuriant. "There's enormous
interest these days in food and wine and the quality of life," he notes.
"People more and more distinguish the difference between caviars."
For example, many consumers know that the Soviets produce three different
kinds of caviar:beluga, the largest, crispest, shiniest and the most
expensive; osetra, which is smaller, sometimes oilier and has a nuttier
flavor; and sevruga, which is even smaller and less expensive. A good
caviar, say experts, should have a shiny texture, not be swimming in oil
nor be sticky, dry or overwhelmed with salt. It should not taste fishy,
for that means it has been exposed to air too long. It should be slightly
salty, delicately fresh and mild. Says Daphne Engstrom, Mat's wife and
partner, "It should taste like a smooth sea breeze."
All this interest suggests that whatever caviar Californians can produce
from their own white sturgeon will find an eager market. And that is one
reason why Elm Bordner is holding his 80-pound sturgeon. It is one of
several taken recently from San Francisco Bay.
Each winter, the researchers go into the Bay and the Sacramento River to
catch wild sturgeon. Ripe females are unusually fat at that time and have
swollen bellies. The scientists make an incision in the abdomen of each
captive fish to confirm its sex and look for eggs. If the fish isn't
ready to spawn, it is stitched back up and returned to the water. If the
female is carrying eggs, the researchers take about 100 of the roe and
test them with hormones to see whether they will start developing. If the
eggs are promising, the fish is kept for days or weeks, until she seems
ready to spawn.
On this occasion, the fish Bordner is holding has been kept in a darkened
tank for several weeks. Early this morning, it began to release shiny
black eggs into the holding tank. The researchers will now open tile fish
surgically and remove the eggs, almost ten pounds of them. In nature,
sturgeon spread their eggs around. The eggs are sticky and adhere to
rocks and aquatic plants until they hatch. But if the fish spawns in the
tank, the eggs will adhere to one another, and those in the center will
suffocate. The researchers will remove the eggs, mix them by hand with
sperm from captive bred males, roll the eggs in fine silt to absorb the
sticky coating, and put them into hatching tanks where bubbling water
keeps them aerated.
A single female may yield 300,000 eggs. The eggs hatch in seven or eight
days into squirming, black, tadpole-like larvae. The Californians have
been remarkably successful in rearing the young. In nature, less than one
percent of the eggs may develop into adult fish. Predators, such as
striped bass, and adverse conditions, such as sudden changes in water
temperatures, take a large toll. But in the tanks, 90 percent of the
larvae survive their first two weeks. They are nurtured by their egg
sacks and don't need to eat.
Within 12 days they use up their egg sacks, however, and must begin to
find food. Then things become more difficult. The researchers offer the
hatchlings the same pellet food fed at hatcheries to young trout. It will
nourish sturgeon, but 40 percent or more of the fish die because they
can't or won't eat the artificial food. And that problem baffles the
researchers. It also makes them worry that when they get females old
enough to breed, there may be nutritional requirements that they don't
understand and which must be satisfied before a mature female begins to
produce eggs. Says Doroshov, "Sexual differentiation is very late in
sturgeon and the mechanisms are largely unknown."
Female sturgeons don't breed in the wild until they are 12 or more years
old, and then, it is thought, they may only breed every third year.
Captive fish grow twice as fast as wild fish because in the constant
warmth of laboratory tanks, they don't slow down their metabolic rates
for winter cold. But it still takes five or six years for a female to
attain the age of maturity. And the West Coast researchers are only in
their fifth year of the project.
Success might launch California into the caviar race with the Russians.
The Soviets have bred captive females, but they have not put the practice
into commercial use. They still harvest wild fish, and that subjects
their industry to wide variety in the quality of roe and requires them to
catch large numbers of fish. A domesticated stock might ultimately be
bred to the uniform quality most consumers seek. Those fish could produce
the eggs and fish meat faster and in much greater quantities at lower
The Davis researchers are now awaiting the maturation of their first
captive female, which they believe should take place soon. They hope by
1986 to spawn their first wholly domestic offspring. After that, the
domesticated stock may spawn an industry, producing both sturgeon flesh
and caviar. "That's a dream at the moment,'' says Ken Beer, a Sacramento
aquaculturist who is a former student of Doroshov's at the University and
is now two years away from having his own domestic female of breeding
age. "But I believe it will happen."
While the scientists are waiting, their efforts may be paying dividends
in another realm. The project produces large numbers of young fish, far
more than the Davis facilities can hold. As a result, most of the
hatchlings are returned to the Sacramento River to join the wild stock.
So far, the researchers have returned some 500,000 fry to the river. No
one yet knows whether these releases are increasing the wild population.
But similar efforts in Russia in recent years have helped to sustain the
Soviet fishery. If the released fry increase the numbers of wild white
sturgeon in California, the practice could be applied to help restore the
badly depleted stocks of lake and short-nosed sturgeon in the East. So,
the management techniques now being developed in California could be a
boon to hard-pressed species in rivers all across the country.
Help Preserve our Aquatic Heritage join the NFC
Check out our Exotic Removal Program and Breeders Program at our website