Project: Interaction of Life History, Fish Size, and Infection Risk on Population-Level Effects of Whirling Disease on Wild Rainbow Trout

Primary Investigator: Thomas McMahon
Project Summary: This long-term study on the Missouri River in Montana combines monitoring of the spread of infection with detailed measures of population response to the disease. The investigators are testing whether spawning and rearing in disease-free areas is a viable management option for maintaining and enhancing trout populations in infected systems. During this study cycle rainbow trout populations remained high and did not drop as a result of whirling disease. However, there are signs of impending population decline as the remaining adults are nearing the end of their life span and the size structure of the adult population shows a much-reduced number of younger fish than in pre-whirling disease years. Expansion of whirling disease into lower tributaries, while not observed to a great degree thus far, could have catastrophic consequences since it appears that most of the adult population is supported at present by recruitment from these tributaries.
Funding Period: 2001-2002
Final Report: McMahon_01-02.pdf
Dataset(s) associated with this project:

There are no datasets associated with this project.