These numbers do not reflect fish removed from the main stem Flathead River during electroshocking.

For those of you who haven’t heard of this project before, it is an effort to remove rainbows and cutthroat ( if less than 90% pure) from the Flathead River drainage to reduce hybridization. The FWP has stated that it is not possible to eliminate hybrid trout from a large, interconnected river drainage such as the Flathead but results from suppression work suggest that it is possible to reduce the number of rainbow or hybrid trout adults enough to maintain populations at a level of 90% westslope cutthroat trout or better.  FWP states “that in large, interconnected river systems, westslope cutthroat trout often display migratory behavior, making long-distance movements among spawning, rearing, and overwintering habitats. Migratory forms of a species are important for maintaining genetic diversity and dispersal among populations and help to protect a population against environmental disturbances, such as wildfire or floods.”

This project has been going on for 12 years now and they are looking to extend it another 10.  It appears that it will have to be perpetual to maintain their goals. The graph above shows that over the course of the project the number of fish removed has been relatively minor.  Hopefully that will be the case in the future. The annual cost for the project is about 10k.

Owning a fly shop and having commercial interest in the Flathead River has me unsure how I feel about the project.  Of course we want to save the cutthroat but…I look at the Bitterroot, Clark Fork, and Blackfoot rivers that are all thriving economic resources (with cutthroat that have all likely been diluted below 90%) and it makes me think why not let it be.  Another part of me asked why the focus on rainbows and hybrids when you have northern pike and lake trout throughout the drainage that have proven to wreak havoc on native cutthroat and bull trout. I guess the problem is that there really isn’t a way to track Flathead cutthroat populations effectively. Flathead cutthroat migrate and are difficult to survey. We can never really know what sort of affect this project or any other will have on population. Even if target goals are met and keep the strain at 90% pure westlope cutthroat, there is no guarantee they will survive at these levels in the Main Flathead. There is no data that suggests it will improve the population numbers or recreational fishing opportunities either. It most likely does the opposite. Hopefully it works out so we can have both.

Adobe Acrobat Flathead River Hybrid Trout Suppression Project

FWP is accepting public comment here.

Flathead River Rainbow.


Jason Lanier
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