Bull trout, a native fish that’s extremely sensitive to changes in water quality, will retain its “threatened” status under the Endangered Species Act, federal officials announced Tuesday.
Over the next year, scientists will also take a closer look at bull trout populations in Washington, Idaho, Oregon, Montana and Nevada to determine whether some need additional protections.
The announcement capped a five-year review of the bull trout’s status.
Bull trout require cold, clean water to thrive.
Their numbers have declined across the West because of grazing, logging, mining, dam building and other development.
The fish are seldom found in lakes or streams with water temperatures higher than 64 degrees. In the Inland Northwest, bull trout are found in Priest Lake, Lake Pend Oreille and Lake Coeur d’Alene, and the St. Joe, Pend Oreille and Kootenai rivers.
“They have the coldest water requirements among fish in the Pacific Northwest,” said Ted Koch, bull trout coordinator for the U.S. Fish and Wildlife Service. “And they migrate fairly long distances.”
Bull trout often spawn in small streams high in the mountains, but head to larger lakes and rivers as they grow. Dams or diverting water from rivers block that migratory path, Koch said.
Locally, the health of bull trout populations varies. Last year, fisheries biologists counted just seven pairs of spawning bull trout in Upper Priest Lake, down from three dozen a few years earlier and more than 100 pairs in the early 1990s, said Scott Deeds, a U.S. Fish and Wildlife Service biologist.
In the upper St. Joe River, the bull trout population is small, but rebounding. Biologists counted about 100 of the fishes’ gravel nests during a survey last year, Deeds said.
In addition to development, bull trout are threatened by non-native species that were introduced to the area, including brook trout and lake trout, Deeds said.
Bull trout were listed under the Endangered Species Act in 1998. Five-year status reviews of listed species have been rare since they were required by 1978 amendments to the act.
The bull trout review was requested by former Idaho Gov. Dirk Kempthorne – now U.S. secretary of the interior – and the Idaho congressional delegation, who contend that the species is thriving in Idaho and that restrictions on development to protect water quality weren’t needed. Environmentalists complained that the review was motivated by politics, not science.
Arlene Montgomery, of Friends of the Wild Swan in Montana, said draft recovery plans for bull trout have been sitting idle since 2002 while the review was initiated.
“It’s time to move on to recovery,” she said.