Thermal Refuge

Discussion in 'Fly Tying, Trout Fishing' started by spinner, Feb 17, 2012.

  1. spinner

    spinner Staff Member

    Many anglers would turn their noses up at this hole. It doesn't look pristine enough for trout water. It has a very unique feature.

    About 16 years ago I was driving home from one of my more pristine trout streams and drove upon a 11-12 year old kid carry an enormous trout along the roadway. I stopped the vehicle and admired the trout. The kid told me:

    "I catch one about this big every year."

    He pointed back from where he came. That bridge there....just upstream there are lots of holes.The kid was fishing with night crawlers. I asked him if he ever used anything else there and said "NO" After a little more question and answer session I learned his family owned the huge stretch of waterway.

    The kid asked for a ride home and I gave him one. I watched as his dad came out and admired the 24ish inch trout. I saw this as my opportunity to get permission. Giving his son a ride home synched the deal. I was given permission and the dad even called his neighbor downstream for me and scored another huge chunk of waterway that bordered it.

    It was late May and the stream was overrun with weeds up to my chest. I fished it a couple times. I took the temperature of the waterway and was quite disappointed in what I measured. In late May the temps were all over 70 degrees. It was not very warm outside either. I decided the big trout the kid caught must have been was a fluke.

    This trout literally had its nose in where the trickle fed in in March. The surrounding stream temperature was 38 and where the trickle fed in was 42 degrees.

    The next year the phone rang. It was the kid from the roadside. He told me had even caught a bigger one. He wanted to know if I wanted to see the huge trout. I drove the 20 minutes to his home and saw the absolute monster. The kid wanted to go out again so we went fishing.

    This stretch is way below the designated trout water. Lots of the holes were snag ridden. The kid promptly caught another decent trout. We fished for another 2 hours. I caught zero and the kid caught a dozen on his worms. Finally the 12 year old let me have a hole first. He pointed out to me where to cast. I chuckled to myself. I thought a 12 year old telling a 45 year old where to cast. I caught a trout almost immediately.

    As we walked back to my vehicle I made a mental note to myself where the kid had caught each trout. Every area had a unique quality.

    I fished the stretch a couple more times that year with little luck. The next early season I went there when the weeds were down and I could see the lay of the waterway better. Each hole that kid caught fish in had a small trickle/spring flowing in just upstream of it. I could not see those trickles because of the tall weeds in May. My March view of this stream enlightened me. I took temperatures and each of these places were "Thermal Refuges"

    This trout was caught within 5 feet of a spring feeding in on March Wisconsin Opener. Springs keep a year round temperature of about 42 degrees. Springs in March are trout magnets due to the water being warmer than the surrounding water.