Below are the recently completed graphs from ODFW showing the results of their Crooked River electrofishing sampling of trout and whitefish last June. See this post from last year for some more context. ODFW will present these results, as well as discuss ongoing tui chub removal efforts in local lakes and their macroinvertebrate study of the Upper Deschutes at the Central Oregon Flyfisher’s meeting on September 18. All are welcome.

This graph illustrates the population estimates for trout and whitefish over the years.   The good news is that trout larger than 8 inches have rebounded from 2023 following the very low flows in the fall of 2022. Whitefish have not. Clearly, the trout population is highly variable based on river conditions but the chart is a little misleading. The peak years around 2014 are when thousands of steelhead fry were being planted in the river as part of the anadromous fish reintroduction program. The hypothesis is that many of these fry stayed in the river rather than migrate to the ocean (they ” residualized”). As you know, redband trout and native steelhead are essentially genetically identical and distinguishing a redband from a residualized steelhead based on quick visual inspection is impossible.

The next two graphs are the length frequencies of trout and whitefish of all passes combined except for the recaptured fish so they don’t get included multiple times.  For reference, 12 inches is 305 mm. So, the majority of trout are under 12 inches, the peak is around 140 mm or 5.5 inches, which makes sense given the results of last year’s survey. Smaller trout survived the low flows better than larger trout. Note that these graphs are of fish larger than 60 mm (2.4 inches) while the first graph is of fish larger than 8 inches.

Interestingly, while the total number of whitefish has declined, they are mostly larger fish.

The final two graphs are the relative weights of trout and whitefish, respectively.  Relative weight shows how “healthy” a fish is compared to other fish of the same species and same size.  The hope is to have scores of 100+.  So, both trout and whitefish in the river are generally healthy.