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It's no secret something has changed at Henrys Lake. It also seems in talking with members, other lakes are struggling as well. Those that have fished Henrys for multiple decades are used to seeing a slow year occasionally, but something is different this time. That difference is it hasn't just been an off year or two but there have been repeated years of low survival rates and poor fishing. When survival or recruitment is low year after year it impacts numbers of fish in the lake and catch rates. Since it seems it's more than just Henrys that's off, it's possible that shifting climate patterns may have something to do with it. It's hard to know but either way it points to survival.
What we do know for certain is that survival during the first winter after the initial stocking is the best predictor we have of the quality of future years fishing. Commonly in lakes, one way to increase survival of stocked fish is to optimize the timing of the stocking when water conditions are most favorable for survival and to increase the size of the stocked fish.
With the goal in mind to increase the survival rate of fish stocked into Henrys Lake, The Henrys Lake Foundation has funded and partnered with Idaho Fish and Game (IDFG) and the Blue Mountain Hatchery in Ashton to raise an additional 55,000 hybrids to be stocked into Henrys Lake. (This is in addition to the 200,000 hybrids IDFG normally stocks.) The goal of this project is to determine the viability of increasing the size at which fish are stocked into the lake to increase survivability and ultimately improve fishing. Half of these fish, or 20,000, were stocked this fall at about three inches in length and the other half or 35, 000 will be stocked next April or May at about seven inches. The photos included with this article are from a fin clipping day at the hatchery where the left pelvic fin was individually removed from the three-inch fish stocked this fall. There will be another fin clipping day held in later October to clip the right pelvic fin of the remaining fish being stocked next spring. Watch for the announcement and come join the fun. IDFG provided snacks and pizza at the last event.
The clipping of the pelvic fin will allow us to identify the two groups ( three-inch vs seveninch) by which pelvic fin was removed. Then we can determine relative survival rates of each group based on the numbers stocked verses the numbers of fin clipped fish recaptured. Most likely to be determined by annual gillnet trend surveys.
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