REXBURG, Idaho – The broad-based surveys showed Yellowstone cutthroat were the most widely distributed, and at 2 million fish, the most abundant trout in the state. Catch trends showed the trout were within 4 percent of the catch rates from 1980 to 2000. The findings showed the cutthroat population trends to be stable. “We also studied genetic purity,” Moore said. Those findings showed that Yellowstone cutthroat trout populations have their own genetic profile in each drainage studied. The research gave the agency a scientific basis for managing the trout to keep the populations steady.
Under its state authority, IFG has two ways to manage fish populations, Moore said. It can regulate the catch by setting seasons and limits and it can adjust the way it stocks hatchery fish. The research backs up the management decisions. And it was the push to keep the trout off the ESA list that provided the data. “In response to the data, we stopped stocking rainbows in high mountain lakes,” Moore said. That’s because the data showed nonnative trout, such as the rainbows, were the biggest threat to the cutthroat population. Catch limits and size limits were also put in place. Before the actions, the species was overfished with a 72 percent mortality rate annually. “Once we got the rules in place to protect the fish, catch is not a limiting factor,” Moore said.
Read more at Bozeman Daily Chronicle















