Protecting a 'Wolf' of a Salmon They call them "river wolves" -- hundred-pound salmon large enough to snack on ducklings and on mice and muskrats fording the rivers. Five species of these huge fish inhabit the river waters of China, Mongolia, and eastern Russia, and all of them are finally on the "red list" of species compiled by the International Union for Conservation of Nature. Newly added to the list are the Hucho bleekeri, listed as critically endangered; the Huch taimen, listed as vulnerable; and the Mongolian (or Siberian) taimen, described for now as "data deficient," meaning that more information is needed. Taimen (pronounced tye-MEHN) salmon can grow to be six feet long. Aside from waterfowl and bite-size mammals, they will eat smaller Pacific salmon that share some of their rivers. They are also long-lived: researchers have found some that they estimate to be 30 years old. Since these animals are typically found in remote locations and are sparsely studied, it is possible that they grow to be much older. The longevity of taimen salmon is part of what makes them an especially important target for conservation measures, said Pete Rand, senior conservation biologist with the Wild Salmon Center, a salmon research and protection group based in Portland, Ore. "They're much more sensitive than other salmon to environmental change" because they are are slow to grow and slow to mate, he said. As a result, they are also slow to adapt to and recover from negative impacts like pollution, overfishing and loss of habitat. The taimen also have evolutionary significance, given that they are thought to be an ancestor of the familiar Pacific Northwest salmon. And they are an important part of the cultural landscape. "They're iconic in Mongolian folklore," said Olaf Jensen, an ecologist with the Institute of Marine and Coastal Sciences at Rutgers University who has studied taimen in Mongolia for the past five years. Dr. Rand led the International Union for Conservation of Nature group that gathered the research on the taimen, much of it by Dr. Jensen, that led to the new listing. He also part of an initiative that led to the initial listing of the two other taimen species, the Sakhalin and Danube, to the red list in 2006. The Wild Salmon Center has focused heavily on conservation in eastern Russia. Areas in Russia and Mongolia where taimen are found are largely undeveloped, meaning there's an opportunity to protect pristine taimen habitat. Inclusion on the red list does not afford the species any specific protections, but underlining their potential vulnerability can make it easier for conservationists to push for regulation through other means. Dr. Rand noted that shortly after the Sakhalin taimen was added to the list in 2006, freshwater protected areas for Sakhalin taimen were put into effect in Japan and Russia. The Wild Salmon Center would like to see similar areas created for other taimen species, but the fish need other protections, too. "Poaching is certainly a pervasive problem," Dr. Rand said. And Pacific salmon fisheries in Asia, tend to land taimen as bycatch. Dr. Rand said he and his colleagues were working with the fisheries to minimize the bycatch problem. Sport fishing is another threat to taimen, but "Mongolia has taken a leadership role in trying to reduce the impacts of recreational fishing," Dr. Jensen said. Fishermen in taimen habitats there are required to release those fish if they catch them, using easily extracted hooks that do little damage to the fish. He plans to continue work with the Taimen Conservation Fund, a Mongolian nonprofit, on monitoring the effects of climate change on taimen. And Dr. Jensen is hoping to help Mongolia train more fisheries biologists - for now, the country can only claim two, he said. He hopes that native pride in the enormous fish will also help spur conservation efforts in Mongolia. "They really have something special there," Dr. Jensen said.