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Harriman Ranch Habitat Use Study

Sep 18, 2013 | Mike Lawson

We’ve made great strides in understanding what is going on with the trout fishery in the Harriman Ranch thanks mostly to research by the Henry’s Fork Foundation. Due to this research we now know that if additional habitat is available during the winter months, more juvenile trout will survive to eventually become the 20 inch tackle busting bruisers that most of us seek when we fish the Ranch. The result of this understanding about the importance of winter habitat has resulted in better negotiated winter flows from Island Park Reservoir, a fish ladder at the mouth of the Buffalo River, a concentrated effort to improve habitat in the tributaries of the river, and more. You can learn more about the details of this effort by visiting the Henry’s Fork Foundation web site.

I have often contemplated the life of an adult Rainbow Trout in the Ranch. There have been times when I have landed a large trout and I have held it in my hands just under the surface and marveled. The thought that the trout was only one of thousands of tiny fry that wiggled out of the gravel to begin their perilous life in the river is marvelous and amazing and difficult to comprehend. As the trout slips from my grasp I wonder if I will ever see him again? Will another angler also experience his existence? How long has he lived? How long will he live? Where does he spend his life during the year? How will he cope with the hazards he will certainly face before another season is past?

A recent research effort conducted by the Henry’s Fork Foundation promises to answer many if not all of these questions. A new study of habitat use in Harriman State Park began this past spring with the capture, radio-tagging, and release of randomly selected adult rainbow trout. The length and weight of each trout was recorded before they were released back into the river at a variety of locations. A total of 40 adult trout participated in this study. A cursory search for these fish showed that 80 percent of them were alive and well in the study reach several weeks after being released, a result of successful tagging methods. This understanding of preferred habitat will help scientists better understand the type of habitat trout need to survive at various times of the year.

Rob Van Kirk working behind the counter in 1982

The research team is headed up by Dr. Rob Van Kirk. We have a good reason to be very proud of Rob. He worked for us in our shop near the end of his high school and through most of his college years. Rob is one of the finest young men I’ve ever worked with in over 36 years in the fly fishing business. He has a passion for our river and its trout. With his educational background and experience he could be working anywhere, yet he has come back to serve the river he loves.


This kind of research is not cheap. It costs roughly $500 to capture and radio-tag a single adult trout. It will be cost effective if anglers, businesses, and other interested parties pony up some cash and sponsor a trout to get this done. Each sponsor will receive a photo of their trout along with its vital statistics, date of capture, capture location, and release location. Sponsors will also be kept informed with the radio transmitted data available. Here at Henry’s Fork Anglers we sponsored a trout that we named Francy. She was a 21.9” female that weighed 3.4 lbs at the date of her release. She was released at the Millionaire’s Pool on June 5 and was last located alive and well still living in the Millionaire’s Pool on July 12. There are still more trout available to sponsor. If you would like to participate click here.


My wife Sheralee and I independently sponsored another trout that we named Pepper.  Pepper was caught, weighed, measured, implanted with a radio transmitter, and released at the stock bridge on June 4, 2013. Pepper is a trophy trout at 23.9 inches long weighing 5.1 lbs. Pepper was last located alive and well on July 10, 2013 at the Avenue of the Giants upstream from the stock bridge.

This project is not only essential but it is fun. With the knowledge that our trout was last accounted for on July 10 I now fish with anticipation that I will cross paths with Pepper. It could have already happened in August when I was whipped quite soundly by a very large trout downstream from Bonefish Flats. At 24 inches Pepper must surely be near the finish of his race. Yet he may survive another winter. Only time will tell.