Science on the SPOT: Green Eggs By The Gram - Sustainable Caviar

Sturgeons, the fish whose eggs are known as caviar, have been around for about 250 million years. These giants are the largest of the freshwater fish and have been known to grow to over 4,000 pounds and live more than 100 years. But it took us only a couple hundred years to deplete their stocks around the world, to the point where most caviar is now harvested from farmed sturgeon.

Caviar is generally associated with the Caspian Sea, the large land-locked body of water surrounded by Russia, Kazakhstan, Iran, Azerbaijan and Turkmenistan. Sturgeon are such big animals and the females produce so many eggs (in the wild, eggs can make up as much as 25 percent of their bodyweight) that historically they were a great source of protein. The caviar was for royalty, with the lightest-colored, blond caviar being reserved for the tsar, in Russia, and the shah, in Iran. But this year, virtually no wild-harvested caviar came out of that region.

Less known is the fact that in the late 1800s, the United States was a purveyor of wild-harvested caviar to the world.

“Here in California, they were harvesting millions of pounds in the late 1800s. And actually there was a town in New Jersey called Caviar, which was the world-leading exporter of caviar,” said Peter Struffeneger, general manager of Sterling Caviar, one of the two companies in California that farm sturgeon for caviar. “But within a span of 30 years they wiped it out. They closed down all fishing from about 1905 to the 1950s, 1960s, depending on which river, for the stocks to recover. And most of them have only gotten back to a point where there’s a limited sport fish for it.”

Two species of sturgeon are native to California: the white sturgeon and the green sturgeon. The green sturgeon is a threatened species and can’t even be fished by sport fishermen. Anglers in California can only catch three white sturgeon per year and need a special card from the state’s Department of Fish and Game to do so. White sturgeons have been plentiful in the Bay Area in 2011, according to this report. But sturgeon poaching remains a problem.

We filmed the caviar harvest at Sterling Caviar’s processing plant in Sacramento County. Sterling Caviar is one of only two companies in California, and a handful around the country, that are raising sturgeon for caviar and meat. (Sterling Caviar ships most of the meat overseas, though some ends up in Brooklyn, where it’s prized by the Russian community).

If you’ve ever wondered why caviar is so expensive (an ounce of Sterling’s highest-grade caviar goes for close to $90 on its Web site), one reason is that even in the best of circumstances, you can only harvest a small amount of it, said Struffeneger. It takes eight to 10 years for Sterling’s female sturgeons to produce eggs. The other reason for the high price, said Struffeneger, is caviar’s unique flavor.

“Maybe a hint of the ocean to it, but not an overbearing saltiness,” he said. “It should hit your taste buds and it actually explodes and you get this ‘wow’ sensation.”

Working with Serge Doroshov, a University of California, Davis, scientist who pioneered sturgeon farming in California, Sterling Caviar has figured out ways to farm sustainably. When the company started out, in the early 1980s, it got permits from the Department of Fish and Game to take white sturgeon from the Sacramento River. But in 1994 the company figured out how to spawn its own females, and since then it hasn’t taken any fish from the wild. And Sterling’s sturgeons are fed fish meal made from sustainably fished sardines and menhaden from Peru and Chile, he added.

For Struffeneger, who has degrees in marine and fisheries biology, the United States isn't doing enough to encourage aquaculture. As a result, he said, the country imports 82 percent of the fish we eat.

Fish farming is the only way forward, he said.

“You can’t increase the supply out of the oceans without doing what happened to sturgeon, destroying the resource,” he said. “One hundred years from now we’ll look back at this as a very transitional period in which we’ve really changed from a hunting-and-gathering society for our seafood to a farming-and-ranching society for our seafood.”