Until about 25 years ago, the Great Salt Lake was the predominant commercially viable source of artemia, accounting for 90 percent of the global supply, according to Philippe Léger, CEO of INVE. New sources were found in the mid-1990s, he added, and today the Great Salt Lake supplies between 35 and 50 percent of the world harvest with Russia, Kazakhstan and China accounting for most of the remainder.
Sorgeloos, who retired three years ago but remains involved in research and expert workshops administered by FAO, completed his Ph.D. on artemia more than 40 years ago, and was involved with the formation of the FAO Artemia Reference Center in 1978 after a severe shortage was noted in the 1960s. At a technical conference on aquaculture in Japan in 1976, many feared there was no future for artemia. How could we develop aquaculture in Asia if small-scale farmers there had to rely on a product from the United States?
Artemia (six species including the common Artemia franciscana and Artemia salina) usage in larviculture traces back to the 1930s, but in the early years the product was mainly used for ornamental fishes, which needed relatively small amounts compared to commercial fish farming operations of today. And 1960s American pop culture enthusiasts will of course remember a hybridized artemia product called Sea-Monkeys, advertised in comic books as a novelty aquarium pet.
While both fish and shellfish larviculture depend on artemia for feed, shrimp producers are by far the largest user. According to Leger at INVE, about 99 percent of shrimp hatcheries worldwide producing quality fry use artemia, so the company has invested heavily in research and technology to help producers stretch the resource.
While overall usage of artemia has increased from 100 metric tons (MT) in 1980 to current levels of 3,000 MT per year, hatcheries are far more efficient today. Whereas artemia used to comprise 35 percent of a hatchery diet with 65 percent dry ingredients, the ratio today is closer to 15:85.
According to the research that Sorgeloos presented at an FAO workshop in Tianjin, China, in November, to produce 1 million Pacific white shrimp (Litopenaeus vannamei) or black tiger (Penaeus monodon) PLs for sale to shrimp farmers, as little as 3 kilograms of artemia are required. It takes roughly the same amount to produce just 5,000 fingerlings of cobia, a large, carnivorous whitefish species (Rachycentron canadum) growing in popularity in the U.S. market.
That overharvesting and climate change will threaten current populations is a shared concern. A new artemia resource popped up about a decade ago, after rivers that once fed the Aral Sea in Central Asia were diverted to cotton plantations. The heightened salinity levels in the Aral unveiled a new source of artemia, but Sorgeloos fears it could fade just as quickly.
While Sorgeloos, Lavens and Legér agree that a global artemia shortage is not imminent, existing resources would benefit from better-regulated harvesting practices, such as those employed in Utah. In Siberia and Kazakhstan, on the other hand, poaching is rampant.
The hearty artemia is euryhaline, meaning it can withstand many different salinity levels, up to 180 grams of salt per liter of water (sea water is 35 g/L, while the Great Salt lake is 150 g/L). As rivers and lakes may vanish due to climate change or human intervention, there is also a chance that freshwater lakes today will eventually turn salty, revealing new artemia sources. However, Lavens and Legér say there are currently no viable candidates.
The full sequencing of the artemia genome, which Sorgeloos and his colleagues in artemia research throughout the world have completed, could help to solve vexing riddles in science and medicine. The gene in artemia responsible for turning life on and off has been studied as a potential treatment to halt the growth of human cancer cells. 781b155fdc