Zoo loses 2 supersize fish

By Martin Weil and Lori Aratani
Washington Post Staff Writer
Tuesday, December 1, 2009

Two of Washington's biggest fish have died in recent days, it was announced Monday. And a third is ill, with an uncertain future.

The fish that died are arapaimas, which were living and swimming in the Amazonia exhibit at the National Zoo. Arapaimas, denizens of the basins of two of the world's longer rivers, the Orinoco and the Amazon, are fittingly among the world's largest freshwater fish. They can grow to be nine feet long.

The fish that died were easily in the seven- to nine-foot range, a zoo spokeswoman said. They were "large fish," said spokeswoman Karin Korpowski-Gallo, and they have scales of a scale that matches their length.

One died Nov. 19. The second was found dead Friday. An autopsy was conducted, but no cause of death was determined conclusively.

However, the zoo said, it is suspected that the fish succumbed to a bacterial infection. Additional tests are being conducted.

The fish had been swimming quietly in the Amazonia exhibit since 1993. Each was believed to be about 17 years old, which is near the maximum lifespan for an arapaima in captivity, the zoo said.

Older fish are thought to be more susceptible to infection, the zoo spokeswoman said.

The fish that is ill is being closely watched and treated with antibiotics, the zoo said. A slight improvement has been noted, according to the zoo, but authorities are guarded about the prognosis.

A fourth of the species, described as an adolescent, appeared to be in good health, the zoo said. But it, too, is receiving antibiotics, as a precaution.

The other fish that inhabit the huge arapaima tank, catfish and pacus, also appear in good health.

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