FRC Completes Phase II of PIT Project

Update: FRC Tags 500 Fall River Wild Trout for Monitoring

Watch Video on Fall River PIT Program!

Fall River Rainbow Trout
Photo Credit: Val Atkinson

Where do Fall River Wild Trout Spawn?

Ever wonder where and when Fall River wild trout spawn? Or how far they migrate throughout 25 plus miles of interconnected springs, lakes, and river? Do all Fall River wild trout originate from the same genetic line, or do we have distinct populations spawning at different times throughout the year?

Through FRC’s Passive Integrated Transponder (PIT) wild trout monitoring program we are seeking answers to these questions so we can help to better understand the river and the fish that depend on it. FRC’s PIT wild trout monitoring program is a partnership with the UC Davis Center for Watershed Science, PG&E, California Department of Fish and Wildlife and California Trout. The PIT Monitoring Program was launched on April 23, 2013 with the group of researchers and professionals tagging 250 wild trout. On July 16th, FRC and its partners led a second round of PIT tagging to bring the total number of trout tagged and sampled for genetics to 500 for the PIT Wild Trout Monitoring Program. A third round of tagging and sampling will occur Fall 2013.

How does it work?

The tracking chips work much like the FasTrak System commonly used for electronic toll collection on bridges throughout the bay area. About the size of a grain of rice, the chip is inserted with a syringe in the abdominal cavity of the fish. Antennas are then placed strategically throughout the greater Fall River system: ideally at the mouth of key tributaries or lake systems, but also on the numerous bridge structures in throughout the main-stem river.  When a tagged fish swims near an antenna, a data logger reads the individual chip code allowing researchers to track movement and location. During the tagging process, each fish is also measured and a small genetic sample clipped from the caudal fin.

Researchers at work into the night on Phase II of the PIT Wild Trout Monitoring Program

Purpose of the Study

 The purpose of this study is to,

  1. Identify key spawning and rearing habitat for protection and restoration
  2. Determine how wild trout utilize existing habitat conditions throughout their life history
  3. Pin point sources of mortality and impediments to migration
  4. Investigate whether genetically distinct wild trout sub-populations exist
  5. Establish accurate wild trout population estimates
  6. Developing a database of science that can help to inform CDFW regulations

 The information collected through this project will be used to prioritize critical habitat areas for restoration and inform and improve wild trout management throughout the Fall River’s 30 miles interconnected spring-fed tributaries, lakes, and waterways. Accurate and comprehensive baseline PIT data will ensure that future restoration strategies will be grounded in sound science and yield the greatest benefit to trout populations.

FRC and its partners will tag and collect genetic information from more Fall River wild trout this coming fall. We will also continue to position arrays in the river so we can better track these fish as they migrate through the system. Keep tuned for further updates about this exciting project.

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