Five Year Mark & Recapture Study
The purpose of the study is to assess the effect of removal of hatchery fish on the native trout populations of the McKenzie River. Hatchery fish stocking was discontinued on this section of river in 2010. Quantitative information about native trout in the lower McKenzie River is limited and existing literature suggests that ceasing hatchery trout releases leads to increased wild trout populations due to reduced competition and angling-related mortality. The Lower McKenzie Wild Trout Population Study (LMWTPS) was initiated in 2010 and is ongoing. 2012 marks the third year of data collection.
To date, ODFW has trained approximately 60 volunteer anglers in data collection protocols and tagging procedures.
The study intends to establish a baseline population of both wild rainbow and wild cutthroat trout, and track those changes over the course of a five-year period.
The study began in March, 2010, and will run through 2014. Fishing effort has been concentrated in the spring and summer.
2010: March 4 – July 15
2011: April 29 – July 15
2012: May 15 – August 10
Fall radio-tracking angling period
2012: October 14-October 22
The study section includes Hendricks Wayside to Bellinger Landing (river mile 24.1 – 19.0).
Hatchery fish stocking was discontinued on this section of river in 2010. The purpose of the study is to assess the effect of removal of hatchery fish on the native trout populations of the McKenzie River.
Anglers (hook & line) and ODFW electrofishing crews fish for wild trout. For trout captured, species, fork length and location is recorded. Captured trout are tagged using uniquely numbered Floy® tags, held until recovered and released near the point of capture. For trout subsequently recaptured, the same information is recorded, with the fish released with the initial tag.
2012 Study Reports:
In addition to expanding our reporting for the 2012 season, we’ve completed a comprehensive audit of the first three years of data. These reports may be slightly different than those from previous years.
2010 – 2012 Distribution of All Fish, Maps (PDF, 0.3mb)
2011 Study Reports:
We’re proud to announce that our 2011 end-of-season reports are now available online.
2011 vs. 2010 Distribution of All Fish, Maps (PDF, 0.4mb)
2010 Study Reports: