The taimen is the largest member of the salmonid family, which also includes trout and salmon. These fish are fierce predators that sometimes chase their prey in packs, a practice that earned them the nickname "river wolves."
They have gray-green heads with streamlined, reddish-brown bodies. And they can be enormous, with particularly large specimens reaching six feet (two meters) long.
Taimen, also called giant Eurasian trout, are notoriously voracious and have a varied diet that includes primarily fish, but also ducks and even mammals like rats or bats. These insatiable fish will also prey upon one another. Some large taimen are known to have suffocated while trying to swallow a slightly smaller member of their own species.
Taimen once swam in rivers from the Russian Pacific Coast westward throughout the former Soviet Union and Mongolia. Today they have been wiped out from much of their range, and significant populations remain only in Russia and Mongolia.
This riverine behemoth is revered by many Mongolian Buddhists as the child of an ancient river spirit, and it has long enjoyed relative peace in Mongolia, where the nomadic culture has traditionally eschewed fishing. But shifting lifestyles in modernizing Mongolia have meant more logging, mining, and grazing, which have harmed water quality in the taimen's range. And fishing, which has driven the taimen to near extinction in China, is beginning to take a toll in Mongolia.
Taimen are spread sparsely throughout their habitat. A study of some 60 miles (100 kilometers) of the rivers where the fish still thrive revealed only about 2,000 "catchable" taimen—those 26 inches (66 centimeters) or bigger. Because of their scarcity, the removal of even a single large fish can be critical.
Today recreational taimen fishing has become an international drawing card and a significant revenue source for regional economies. Mongolian officials, together with several nonprofit organizations, are trying to find a balance to curb poaching yet promote regulated fishing and the revenue it brings.
Taimen range 
