Officials to Discuss Whitefish in the Big Lost River

Biologists with the Idaho Department of Fish and Game and the USDA Forest Service will be holding a public meeting this month to discuss the current status of the fish populations, with an emphasis on mountain whitefish, in the Big Lost River drainage. Over the last several years biologists have been working to learn more about the native fish of the Big Lost River. "This research has indicated that mountain whitefish and sculpin are likely the only fish native to the river Big Lost River basin", said Jim Fredericks, the Regional Fishery Manager for IDFG. "This work has also indicated that the mountain whitefish in the Big Lost River are unique compared to other whitefish populations." Bart Gamett, a fishery biologist with the USDA Forest Service, stated, "We believe that mountain whitefish entered the Big Lost River basin through an ancient connection with the Snake River and it appears they have probably been isolated in the Big Lost River basin somewhere between ten thousand and several million years." He continued, "This isolation has resulted in a fish that is distinct from other mountain whitefish." Public concerns over apparent declines in whitefish populations and the unique nature of the fish have led biologists to evaluate the current status of whitefish in the Big Lost River basin. For the past two years, the IDFG and the USFS have conducted population estimates for trout and mountain whitefish in the Big Lost River. Although trout populations generally appear to be in good shape, the picture wasn't so good for whitefish. "There is a very significant decline in both number and distribution of whitefish in the drainage," said Fredericks. To estimate past distribution, biologists used past fishery surveys and a variety of information from area residents. Mountain whitefish were once found in about 216 miles of stream in the drainage. Based on the recent fishery surveys, they occupy only around 47 miles or 22% of the historical range. "We know these fish were historically present throughout the river and most of the major tributaries," said Fredericks. "However, data collected over the last couple of years indicates they have disappeared from much of the river and several major tributaries including Antelope Creek, Wildhorse Creek, Star Hope Creek, and North Fork." Although no one can be sure how many whitefish once occupied the river and its tributaries prior to settlement by European man, the number (over eight inches) is believed to have been around 500 per mile. The recent surveys indicate the population of whitefish over eight inches in the East Fork is around 18 per mile and the population below the dam is about 30 per mile. Although biologists are still working on a total population estimate, the low density combined with the current distribution suggests the overall population is a small fraction of the historical number. The decline in recent years is not entirely understood, though drought and the demand for available water have clearly played a very large role. "Much of the area that was historically occupied by whitefish is now dry," said Fredericks, "for example, we know the Big Lost River supported a healthy whitefish population from the Blaine Diversion out onto the desert below Arco, and now that area is completely dry for much of the year. The problem with the lower river is pretty obvious. However, populations have also declined in many areas not affected by water withdrawal". Officials with IDFG and the USFS want to share what they've recently learned about whitefish with area residents and begin discussing what can be done to help the population. "Right now, we've got some obvious problems, but there is still a lot we don't know about these fish," said Gamett, "We need to learn more about what's behind the declines, but at the same time we need to start talking about what can be done to make the situation better." Fredericks agrees. "As we learn more about migration patterns and habitat use in the next year, we may identify some inexpensive and effective actions that can implemented to improve the whitefish population." The meeting will be held at Mackay High School on Wednesday, May 26th from 7-9 PM.