By Jessianne Wright
BOZEMAN – One year after the massive Yellowstone River fish die-off, biologists are once again finding dead fish in the river. Montana Fish, Wildlife and Parks staff have conducted survey and monitoring floats on the river between Livingston and Springdale, but are finding significantly fewer dead fish than were found last year.
According to an Aug. 31 press release, this recent fish kill was caused by proliferative kidney disease, the same disease that resulted in the deaths of thousands of mountain whitefish last year.
FWP staff floated from Livingston to Grey Bear Fishing Access Site on Aug. 22 and 23 and counted 76 dead mountain whitefish, two dead long-nosed suckers and one dead brown trout according to a press release. On Aug. 24, biologists floated from Grey Owl Fishing Access Site to Pine Creek, which was the hardest hit by last summer’s outbreak of proliferative kidney disease, and monitoring crews found 19 dead whitefish.
On Aug. 29, FWP crews once again floated the river and stated in a release that “results were encouraging.” The surveys between Livingston and Springdale turned up fewer dead fish and stable water flows and temperatures. Biologists collected 13 recently deceased whitefish and seven that had been dead for some time.
FWP reports that biologists have found approximately 165 dead whitefish during these recent monitoring floats. Last year, upward of 1,900 whitefish were found dead on one bank of the river.
“We’re not considering any closures or restriction, but are asking that anglers not target whitefish for the time being,” said Region 3 fisheries manager Travis Horton in an Aug. 30 release.
Last August, 183 miles of the Yellowstone River were closed for about two weeks to all water activities as thousands of whitefish and some rainbow and Yellowstone cutthroat trout were found dead in the river. The fish mortality was caused by a parasite that causes proliferative kidney disease, and appears to be linked to high water temperatures, low flows and general fish stress.
“With cooler water temperatures and higher flows, those conditions aren’t present this year,” FWP stated in the Aug. 30 release. “Water temperatures have remained cooler and flows are above average. … These environmental differences could result in a much different scenario and outcome compared to last year’s fish kill.”