The healthiest populations of taimen are found in the Uur River, above, and the Eg River in northern Mongolia's Zerleg, or "Wild," district.

While overfishing in neighboring China has brought the taimen to the brink of extinction there, Mongolians are traditionally not fishers, which has helped protect that country's taimen population.

But as Mongolia's economy develops and road conditions improve, recreational fishing in remote regions like the Eg-Uur watershed is becoming more popular.

To protect the taimen, conservationists such as Zeb Hogan, who leads National Geographic Society's Megafishes Project, advocate a concession system where private companies would do the fishing exclusively and would be required to release any fish their clients catch back into the river.

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