Everybody knows tomato prices are up because this winter traveled so far south, but what’s up with salmon prices?

Spot salmon prices in the United States hit $4.55 a pound earlier this month, up from $2.77 a year ago, according to a market tracking service.

Supply is short because a virus in Chile’s salmon farms is causing widespread anemia in its Atlantic salmon stock.   Chile will deliver only 90,000 tons to the market this year; down from over 400,000 tons two years ago–all due to the devastating virus.

The U.S. Food and Drug Administration (FDA) this week said that even though the virus is killing the salmon, it is safe to eat.  “We have no information that any harm can come from eating Chilean salmon,” an FDA spokesman said.

Wal-Mart, which was the largest purchaser from the Chilean fish farms, ceased buying Atlantic salmon from South America last summer as the virus problem worsened.

Atlantic salmon from Chile last year accounted for about 30 percent of the U.S. market.

Infectious salmon anemia (ISA) first stuck fish farms in Norway in the mid-1980s.  It spread to New Brunswick and Scotland by the late 1990s.

It is a flu-like virus that gets into the blood stream of Atlantic salmon.  There is no cure.  It causes anemia and death.

The European Union and Canada require that infected stocks be destroyed.  ISA outbreaks have cost Canada, Norway, and Scotland millions of dollars a year.

In those countries, measures are being taken to require minimum distances between fish farms and to limit the movement of ships and personnel around sites.

Farm fish critics say ISA is spread by water cage systems that are too crowded and the misuse of chemicals.  The Atlantic salmon is indigenous to neither South America nor British Columbia, where they were introduced in fish farms.

With its salmon industry devastated, Chile is considering new regulations on fish farming.  Before those efforts produce any results, however, world stocks of Atlantic salmon will drop to levels not seen since 1990, experts say.

The outbreak is centered in fish farms off southern Chile’s Chiloe Island.

The farm-raised salmon sickness is coming just as the far more favorable wild salmon has been making a bit of a recovery.  Last fall, for example, about 700,000 Coho salmon returned to the Columbia River system in the Pacific Northwest.  The National Oceanic and Atmospheric Administration (NOAA) is predicting another large return in 2010.