Shocking a section of the Salmon Trout River

Katie Renschen with a brook trout

In an ongoing effort to rehabilitate the native coaster brook trout (Salvelinus fontinalis) in Lake Superior, Ashland National Fish and Wildlife Conservation Office (NFWCO), Michigan Technological University, and the Michigan Department of Natural Resources are studying and assessing the fish's migrations and biological characteristics.

During the weeks of June 9^th, and June 16^th, Katie Renschen assisted Dr. Casey Huckins from Michigan Tech University and Dr. Edward Baker from the Michigan DNR in backpack electrofishing sections of the Salmon Trout River located in the Huron Mountains northwest of Marquette, Mich.  The Salmon Trout River is the site of the last known remnant population of coaster brook trout on the south shores of Lake Superior.

The goal of this survey was to assess and collect data on the population of resident brook trout in the river.  Specifically, we were looking for brook trout greater than 200 mm.  In theory, these fish would be resident brook trout, and not coasters.  Coaster brook trout at this size are thought to have already moved out of the river and into Lake Superior.  By collecting data and genetic samples on resident brook trout, genetic analysis can be done between resident brook trout and coaster brook trout in hopes of finding genetic differences between the two.

During the two weeks of sampling, over 5 river miles were covered.  However, the number of resident brook trout captured was minimal.  Not more than 5 fish greater than 200 mm were captured.  There were several “questionable” resident brook trout caught ranging from 160-180 mm, and genetic samples were taken on them as well. 

Studies and assessments on the Salmon Trout are ongoing; recently, a weir and camera were also set in place on a section of the river to further monitor the life and movements of the coaster brook trout.