Web edition: March 1, 2006
In a month or two, sturgeon will begin spawning runs throughout the Northern Hemisphere. Although many people eat the meat of these fish, it's the animals' pearly black eggscaviarthat have the most value. Depending on the species and the quality of its roe, retail prices for wild-sturgeon caviar can reach $150 an ounce. The fact that a single female can carry 100 or more pounds of roe means that landing even one of these fish can prove enormously profitable.
Probably too profitable.
Populations of all 25 modern species of sturgeon have declined dramatically in recent decades, primarily because they have been overfished for their roe. The female fish is usually sliced open and her roe-bearing organs removeda lethal processbefore the eggs gets overripe.
The decline in sturgeon populations has become so dire that on Jan. 3, administrators of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES, banned international trade in caviar from the world's three top-producing river basins: the Caspian Sea basin, the Black Sealower Danube River basin, and the Amur River basin of Russia and China.
The ban has had little practical significance yet, since the yearly sturgeon harvests in those areas won't begin until about April. In the long run, however, the new limits promise to have dramatic impacts. By shutting down sales of caviar from this region to major consuming nations, including the United States, the ban could cut fish harvests. That would give an especially needed respite to the fish that's the source of the most-prized caviar: beluga sturgeon. Its numbers in the Caspian and Black Sea areas have declined by 90 percent just since the 1980s.
The CITES ban "is good news for sturgeon that are on the brink of extinction, especially the Caspian Sea beluga," argues a statement issued by Caviar Emptor, a coalition of the University of Miami's Pew Institute for Ocean Science, SeaWeb, and the Natural Resources Defense Council. The consortium had lobbied hard for giving this wild sturgeon a breather from heavy fishing.
Some other scientists and regulators have expressed less enthusiasm, pointing out that although legal harvests will diminish in the three affected regions, the ban will probably have little impact on illegal harvests of the fish. Moreover, as legal markets for European and Asian sturgeon dry up, a continuing demand for caviar could put unhealthy pressure on nontraditional sources, such as wild North American species.
There's also the potential for increased fraud to thwart the ban, notes David H.W. Morgan, who heads science support for CITES. For instance, he says that some eggs from wild-caught sturgeon may be passed off as the product of farmed fish, which are exempt from the new ban.
In other words, he and others acknowledge that, although the CITES action is an important and positive move to conserve overfished sturgeon species, it's no panacea.
Sturgeon are the largest freshwater species of fishor at least they have the potential to be. These animals can live a century, periodically producing young from about age 20. With each year, a sturgeon increases in size. Before the age of commercial fisheries, some landed specimens spanned 20 to 30 feet and weighed a ton or two. At least one beluga was caught bearing some 900 pounds of roe.
Those days are over.
Fishing has become so intensive that sturgeon no longer reach ripe old ages or mammoth proportions. Several sturgeon species now face imminent extinction, according to a report in the September 2005 Fish and Fisheries by Ellen K. Pikitch and Phaedra Doukakis of the Pew Institute, and their colleagues. Moreover, these researchers report that "few viable [commercial] sturgeon fisheries remain" (SN; 3/4/06, p. 138: Available to subscribers at http://www.sciencenews.org/articles/20060304/bob9.asp).
In the 19th century, the United States had the largest sturgeon catch and exported caviar widely. By the early 20th century, most large, highly profitable females had been caught, leading caviar marketers to turn to the huge untapped reservoirs of European and Asian species. By around 1900, Russia had ascended to become the premier caviar source, harvesting seven times as many sturgeon annually as the U.S. ever had, Pikitch's team notes.
Russia's neighbors also moved to commercialize sturgeon. Before long, nations bordering the Caspian SeaIran, Kazakhstan, Russia, Azerbaijan, and Turkmenistandominated world sturgeon catches. However, their yields peaked in 1977. Global yields of sturgeon that year, mostly from the Caspian, exceeded 30,000 metric tons of the fish. Harvests there and elsewhere have been on a steep decline ever since. By 2002, the most recent year for which data were available, global legal harvests of wild sturgeon constituted a mere 2,000 metric tons of fish annually, Pikitch and her colleagues report.
No firm figures exist on the extent of sturgeon poaching, Morgan observes, as it's by nature covert. However, the new report in Fish and Fisheries notes that poaching probably exceeds legally reported harvesting.
The CITES ban, which will be observed by the United States, is on all international trade in caviar from the three areas. It follows a narrower U.S. ban, set to start this week, focusing on the importation of beluga-sturgeon products from the Caspian Sea and neighboring regions. The U.S. Fish and Wildlife Service (FWS) announced last October that it would implement the action under the U.S. Endangered Species Act. A year earlier, the fish became one of the few nonU.S. species to be protected under the U.S. law.
The FWS move could be powerful, because 80 percent of legally traded beluga caviarfrom the 11 nations that today make up the species' home rangemoves through exporters in the United States. The FWS announced that the ban would be withdrawn when nations in the animals' home range had demonstrated they were better managing the various beluga species and policing their overfishing.
Unlike the CITES ban, the U.S. beluga ban prohibits U.S. trade in caviar from even sturgeon farms throughout the fish's home range. Offering no farmed-fish loophole, FWS explained, appears "the best way to engage those nations in cooperative conservation for the species." The U.S. rules also limit the ability of caviar exporters to pass off any wild-caught caviar as roe from farmed beluga sturgeon.
Pikitch notes that it was a petition by Caviar Emptor that forced FWS to consider listing the beluga sturgeon under the Endangered Species Act. "We thought that [a U.S. listing] might spur other nations to take similar unilateral actionand might even spur CITES to do something." The action seems to have had the desired effect.
The U.S. action "was really a bold move" that flew in the face of much international opinion, says Pikitch. Indeed, the federal agency got many criticisms of its proposal during the period it was open for public comment. Pikitch credits FWS's decision as being a strong factor motivating CITES to impose its broader regulations on the caviar trade this year. CITES' limit not only affects all species within the major sturgeon-exporting regions of Europe and Asia, but also trade between every one of the treaty's 169 member nations.
However, since CITES' legal role is restricted to international trade, Morgan explains, "that limits the depth to which we can get involved." Under terms of the new ban, any country in the affected river basins can continue to market sturgeon products domestically. However, even this local caviar must carry a label showing its origin. "That's a novelty for CITESto get involved like this in domestic trade," Morgan adds. "It's intended to permit some traceability of products."
The rub, he acknowledges, is that many caviar-importing nations "have not, to our knowledge, put in place these [labeling] measures to help make sure that any caviar and other sturgeon product that's on the market is of legal origin." That blind spot, Morgan says, "leaves a space for caviar of dubious origin to circulate in the marketplace . . . and makes it very difficult for consumers, for instance, to know whether they're buying a legal product."
Moreover, he adds, "fraud is a possibility." Once legal labels have been designed, Morgan explains, "they can always be counterfeited."
Doukakis, a fisheries biologist who has focused on sturgeon genetics, points out that fraud is far from a theoretical concern. In 1998, "we did a market survey to look at whether labels on sturgeon caviar tins were accurate with respect to species of origin," she notes. Based on genetic analyses, her team showed that at least one-quarter of 96 commercially available lots of caviar purchased in New York City were mislabeled.
Sometimes lower-quality caviar was substituted for beluga, which "is not surprising," says Doukakis, because wild-beluga caviar is desired but exceedingly rare. In two cases, she and her colleagues found that the highly endangered ship sturgeon (Acipenser nudiventris) had been labeled as Russian sturgeon (Acipenser gueldenstaedtii).
Since this research was conducted, the demand for caviar has only increased. With the new ban, she worries that pressure to mislabel caviar could skyrocket. Caviar from wild Siberian sturgeon (Acipenser baeri) in the Caspian might be fraudulently identified as Siberian caviar from legal aquaculture operations. Indeed, Doukakis told Science News Online, when her team interviewed U.S. sturgeon farmers a year ago, "a few told me they were getting inquiries from people to purchase either empty [caviar] tins or labels."
Beginning this year, the Mote Marine Laboratory in Florida will begin selling some of its first crop of caviar from Siberian sturgeon raised at the lab's commercial-scale test facilities, notes project leader Jim Michaels. His team is tailoring aquaculture techniques for this non-native species, which it intends to pass along to local fish farmers.
Critics of the new CITES ban say that another unintended byproduct of the action could be exaggerated demand for caviar from species that haven't been heavily exploited in the past.
For instance, news organizations have reported that hauls of shovelnose sturgeon (Scaphirhynchus platorynchus) from the Mississippi and Missouri rivers have been skyrocketing in recent years, fueled by domestic U.S. demand.
Fisheries biologist Diana Papoulias of the U.S. Geological Survey calls recent increases in harvests of this species "berserko." She's been studying shovelnose sturgeons and now feels an imperative to work as quickly as possible. "With the pressure on habitat destruction and from fishing," she says, "I don't think this fish will be here in 20 years." Right now, she observes, "caviar fishermen can't wait to take these fish because the market has become bottomless."
Ironically, she notes, her studies have found that all Midwest sturgeon of reproductive agewhich means individuals at least a couple of decades oldare heavily contaminated with toxic contaminants. The pollutants, which are most concentrated in the roe, include DDT, polychlorinated biphenyls, and chlordanea banned pesticide once used to control termites. Her team discovered the contamination while studying the high and apparently increasing risk of hermaphroditism in shovelnose sturgeon. Some animals have shown up in recent years containing both mature eggs and sperm.
Though she suspects that hormone-mimicking pollutants may play a role in these sexual impairments, she can't prove it. What she does know is that in terms of their contamination, the quality of eggs "is pretty bad."
Despite all the problems with sturgeons and their roe, few people say caviar should be outlawed. Even Caviar Emptor endorses responsible trade in the fish eggs. "Caviar varieties produced by sturgeon and [related] paddlefish farmed in the United States offer excellent taste and are environmentally sustainable," the organization contends. For those who are even more gastronomically adventurous, the group suggests trying roe from farmed trout and wild Alaskan salmon.
Web site: [Go to]
Pew Institute for Ocean Science
126 East 56th Street, Mezzanine
New York, NY 10022
David H.W. Morgan
Convention on International Trade in Endangered Species of Wild Fauna and Flora
Maison Internationale de l'Environnement
Chemin des Anémones
CH-1219 Châtelaine, Geneva
Web site: [Go to]
U.S. Geological Survey
Columbia Environmental Research Center
4200 New Haven Road
Columbia, MO 65201
18 Bd de
Web site: [Go to]
Ellen K. Pikitch
Pew Institute for Ocean Science
126 East 56th Street, Mezzanine
New York, NY 10022
2006. Caviar exporters urged to strengthen controls & promote sustainable fishing. United Nations Environment Programme press release. Jan. 3. Available at: [Go to].
2005. Current status of beluga sturgeon: Summary of scientific literature. Caviar Emptor Web site. Available at [Go to].
Brainard, J. 1998. DNA fingerprinting to track caviar. Science News 154(Aug. 22):116. Available at [Go to].
Carey, R.A. 2005. The Philosopher Fish: Sturgeon, Caviar, and the Geography of Desire. New York: Counterpoint.
Raloff, J. 2006. Saving sturgeon. Science News 169(March 4):138-140. Available to subscribers at [Go to].
______. 2000. Downtown fisheries? Science News 157(May 13):314-316. Available at [Go to].