Trout Myths Revealed

[hookncook]

We’ve all seen pictures of monster Brown Trout caught out of the Driftless Region, and wonder how in the world could a trout get THAT big in a Driftless Region Stream.

That was one of the topics covered in the 5th annual Driftless Area Symposium last month. William French from the University of Minnesota gave presentations on winter trout feeding habits and cold water insects.

Very little is known about winter habits of trout. Because most of the Driftless Region is not fish-able due to regulations people don’t really observe trout habits. People focus on spring, summer and fall habits because it best pertains to their fishing preferences and knowledge.

French’s research covered winter life of a Driftless Stream from February to March. They used streams based on three categories: Slow, fast, and average streams (reflecting to trout growth); then they selected 4 streams of each of the respective categories. The crew would tag individual fish through out Minnesota and measure them three times. The crew also investigated food preferences for the trout during the winter months.

During the winter, stream dynamics change from colder water at the mid section and warmer water at the head waters and base waters to the polar opposite for warmer water in the mid section and cooler water in the head and base waters as springs tend to produce warmer water heated up by geo thermal heat. In the summer, air warm up the surface water and the springs produce water at below ground temperatures.

The crew noted trout growth in all the streams and winter trout feeding habits are based on insect availability. During the winter insects that have evolved to withstand colder water temperatures occur seasonally, and the trout capitalize on the hatches or availability of the seasoned insect.

Streams like the Pine River and Elk Creek in South Central Wisconsin and Hay Creek in Minnesota produce larger fish because the water temperatures are higher and they are prone to produce more insect life and winter food to enhance winter growth. Winters over the last couple years have been unseasonably warm, allowing streams to be warm and producing an increase of winter insects.

Streams like Timber Coulee Creek in Wisconsin are traditionally cooler and are less prone to produce significant insect activity and produce smaller fish due to slower growth rates. Another factor of trout growth is genetics. Stock strain trout tend to be smaller than wild strain trout. French’s research isn’t over. The crew plans on studing 36 streams over the next 12 years.

Overall, winter trout do not suffer. Trout feed, grow and flourish in the harsh winters of the Driftless Area.

[reinhard1]

when i was a kid up in Duluth Minnesota i lived near twin ponds in the center part of the city up on the hill. there was a little creek that came out of the ponds. this creek was small and went under streets in tunnels on its way to the bay. you could jump accross the creek in many places. one time i went in the tunnel under one of the streets. big enough so you could stand up and you could see the other end of the tunnel. just a little pool in the middle, not very deep and it was fairly dark in that tunnel.

just had a spinning rod and a nightcrawler. put the crawler up in the pool and felt a tug and soon i had a 3 pound brown trout in my hand. like you said they do survive in strange places and in water that you would think would freeze out. i have never forgotten that moment. normaly we just cought small brookies if we were lucky enough just to do that. good luck.

[itchmesir]

Wait... Bugs? Big trout eat bugs? I thought they only ate minnows and small fish.. that's why spinners only catch big trout....

Nice read... Makes sense.. and the research seems to be following the scientific method

[hookncook]

"what.. Trout bugs.."

that was question that came up in the forum. They did not see predation in large trout. Some trout had consumed sculpins but that was in very few subjects. In that study, the data supported that insects was the primary diet for the trout surveyed.

And they did survey a very large trout captured on Hay Creek.

[itchmesir]

So what is the background of this mr french... is he a ecology/biology major? Teacher? TU guy?

[hookncook]

That's a good question.

From my notes, he's a student there but they don't have his credentials listed. The project is funded by the US Forrest Service, MN DNR, Chironomiade Research Group, USGS, U of M Conversation Biology Graduation Group, Minnesota Cooperative Fish and Wildlife Research, the Environment and Natural Resources Trust Fund.

[bobbymalone]

he's a PhD student in the Conservation Biology program.

As a student, he probably doesn't have 'credentials'

that's not to say he doesn't know what he's talking about.

[hookncook]

"that's not to say he doesn't know what he's talking about."

I think given the atmosphere and genre' of his presentation, I would be fearful to give a presentation to a group of that caliper and not know what I"m talking about.

What I took from the presentation:

Trout flourish over the winter months (obviously)

Stream patterns change with the seasons water temperature wise

It solidified that water temperatures and genetics do play a role in a fish's grown. Water temps play an indirect role in that it affects food and genetics play role physically.

I'm really glad they used more than 4 fish to use as study subjects.