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So far Henrys Fork Foundation has created 96 blog entries.

35th Anniversary — Lessons Learned. Part 1: Angler Perceptions and Economic Value

  35th Anniversary – Lessons Learned   Part 7:  Angler Perceptions and Economic Value   Using science to understand what anglers value or to quantify the economic contribution of fishing to the local economy is a relatively new component of HFF’s programmatic work. A series of angler attitudes surveys began in 2008 – repeated in 2014 and redesigned for 2016, 2017, 2018 – to get a better sense of factors like angler satisfaction with their fishing experience, angler characteristics, and any changes in attitudes between years. The first attempts to quantify economic value of fishing on the Henry's Fork began in the late 90s and was repeated in 2004 and again in 2016-2018. Dr. Cliff Nowell of Weber State University was involved in design, implementation, and analysis both for the original study and the most recent.   Here are a few highlights of what we’ve learned about angler perceptions and the economic value of fishing on the Henry’s Fork:     Angler Attitudes Studies:  The “median” Harriman angler: comes from Idaho, Utah, or California; began fishing the Ranch in 1995; fishes the Ranch 6 days/yr; fishes other sections of the Henry’s Fork 3 days/yr, and catches zero fish per day on the

35th Anniversary — Lessons Learned. Part 1: Angler Perceptions and Economic Value2019-04-19T20:06:49+00:00

Water Supply Above Average for Third Consecutive Year

Record precipitation in February moved snowpack from 80% of average on February 1 to 110% of average on April 1. Watershed-wide natural streamflow for April through September is forecast to be 105% of average, compared with 104% of average in 2018. Delivery of water from Island Park Reservoir is predicted to begin around July 1 and remain in the range of 800-1200 cfs during July and August. Because of very good inflow, the reservoir is expected to end the irrigation season around 80% full, compared with 72% full in 2018. Higher water levels in Island Park Reservoir have numerous, scientifically documented benefits to the Henry's Fork fishery, prompting HFF to continue to expand the  number of methods we use to limit delivery of water from the reservoir. A Record-Setting February The watershed as a whole receieved at least 0.1 inch of precipitation on all but seven days during the month of February, and several precipitation records were broken in the watershed and elsewhere around the state during the month. Over the whole watershed, the record-setting month moved water-year precipitation from 85% of average to 120% of average and snow-water-equivalent (SWE) from 75% of average to 120% of average. March turned

Water Supply Above Average for Third Consecutive Year2019-04-10T15:59:47+00:00

35th Anniversary — Lessons Learned. Part 6: Water Quality

  35th Anniversary—Lessons Learned.   Part 6:  Water Quality   The abundance and size of wild trout, as well as the abundance of organisms on which trout feed, are determined in large part by river flow and the physical and biochemical properties of the water ("water quality"). Fourteen U.S. Geological Survey stream gage stations (see map) and dozens of other gages on canals and reservoirs provide a continuous record of streamflow throughout the watershed. However, prior to 2014, our understanding of physical and biochemical processes such as sediment- and nutrient-cycling in the Henry’s Fork lagged far behind that of hydrology. That is why HFF launched a long-term water quality monitoring program in 2014. The goals of this project were to: 1) monitor long-term changes to important water-quality attributes in major river reaches and tributaries, 2) accumulate fine-scale data that provides the underlying chemical, physical, and biological context for interpreting results of site-specific research and monitoring, and 3) establish the capability to rapidly collect pre- and post-project data for the purposes of evaluating effects of new facilities and management actions. HFF has established a network of 11 water quality monitoring stations at strategic locations in the watershed. At each station, a sonde records

35th Anniversary — Lessons Learned. Part 6: Water Quality2019-03-28T22:03:24+00:00

35th Anniversary – Lessons Learned. Part 5: Island Park Reservoir

  35th Anniversary – Lessons Learned.   Part 5: Island Park Reservoir   Many already have a sense that Island Park Reservoir plays a significant role in water quality, streamflows, and the fishing experience downstream, but here are 4 key lessons learned about the reservoir since HFF's founding in 1984:     1.  HFF's research on effects of Island Park Reservoir on water quality and the fishery downstream shows that keeping the reservoir as full as possible for as long as possible results in cooler summer-time water temperatures below the dam, lower turbidity, lower suspended sediment export from the reservoir, and higher winter flow. Thus, mid-summer fishing experience and long-term habitat quality and trout recruitment all benefit from a full reservoir.   Low storage levels in IP Reservoir lead to higher turbidity downstream of the dam.   2.  A full reservoir also increases the chance of a beneficial spring freshet that can move sediment out of certain river reaches and provides habitat benefits for trout and aquatic insects all the way down to St. Anthony.     3.  A higher summer reservoir level provides more summer habitat for fish in the reservoir, which contributes more fish to the upper river.  

35th Anniversary – Lessons Learned. Part 5: Island Park Reservoir2019-03-28T08:06:48+00:00

35th Anniversary — Lessons Learned. Part 4: Hydrology

  35th Anniversary -- Lessons Learned.   Part 4: Hydrology   Photo by James Chandler.   Deep aquifers on the Yellowstone Plateau are the primary source of streamflow in the upper Henry’s Fork subwatershed (i.e., the watershed upstream of Ashton). Big Springs, Warm River, and Buffalo River are the three largest spring-fed tributaries to the Henry’s Fork. Snow falls on the Yellowstone Plateau, then recharges the aquifer as it melts. Due to the thickness (up to 1,000 feet) and geology of the aquifer, it takes 50-100 years for an individual water molecule to make its way through the aquifer and emerge at the springs. Fortunately, the response time of flow from the springs is much shorter, around 3 years. This response is due to the pressure of snowmelt entering the aquifer at the top and pushing water that’s already in the aquifer out the bottom at the springs.   Here are three key lessons learned about the hydrology of the Henry’s Fork:     1.  Response time of flow at Big Springs to precipitation on the Yellowstone Plateau is about 3 years. Water flows out the bottom of the aquifer at Big Springs depending on pressure at the top of

35th Anniversary — Lessons Learned. Part 4: Hydrology2019-03-27T20:29:53+00:00

Ora Bridge Construction and HFF Water Quality Monitoring

Ora Bridge. Photo by James Chandler Photography.   Plans to replace and redesign Ora Bridge have been in the works for 5 years. As this is a significant project, discussions and preparations took a great deal of time; from planning and public meetings, to bidding out the project and finalizing details with the contractor. The project has seen some delays and is now ready to begin (as soon as the weather cooperates). HFF’s role in the process began 5 years ago thanks to Fremont County keeping us in the loop on the project. Senior Scientist, Rob Van Kirk attended several meetings and provided feedback along the way. In January 2015 and again in late 2017, HFF, alongside Idaho Dept. Fish & Game, argued strongly for:  1) no disruption to fishing access, and if a temporary closure is absolutely necessary for safety, delivery of large equipment and materials, or unforeseen emergency, that it occur between July 15 and September 1, at least 24 hours’ notice should be given, and the closure should be no more than 2 consecutive days; and 2) no in-water construction prior to July 15th to protect Rainbow Trout spawning and to minimize disruption to the angling season.

Ora Bridge Construction and HFF Water Quality Monitoring2019-03-23T08:06:33+00:00

35th Anniversary — Lessons Learned. Part 3: Aquatic Macroinvertebrates

  35th Anniversary – Lessons Learned   Part 3:  Aquatic Macroinvertebrates   Aquatic macroinvertebrates—insects and other creatures that live in the stream bottom—feed trout and are the basis of fly-fishing on the Henry’s Fork, but they are also important indicators of aquatic habitat quality. Mayflies, stoneflies, and caddisflies are sensitive to water pollution and habitat degradation, making them so important to the assessment of water and habitat quality that it has its own acronym among aquatic ecologies – EPT; for the three taxonomic orders Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies). Higher relative abundance of EPT taxa indicates better water and aquatic habitat quality. Here are five of the most critical things HFF has learned about macroinvertebrates on the Henry's Fork.   1.  Unfortunately, HFF does not have the needed historic data to compare how individual species have changed across long periods of time. We can only assess the data we have collected from 2015-2018 (2019 data is being analyzed as we speak) and trends across those years.   2.  In general, we know that overall health and percentages of mayflies, caddisflies, and stoneflies (%EPT) on the Henry’s Fork is good.       Percent mayflies, stoneflies, and caddisflies at five

35th Anniversary — Lessons Learned. Part 3: Aquatic Macroinvertebrates2019-03-21T20:06:57+00:00

35th Anniversary — Lessons Learned. Part 2: Buffalo Fish Ladder

  35th Anniversary -- Lessons Learned Part 2:  Buffalo Fish Ladder     After the construction of the Buffalo River Hydroelectric project in the 1930s, fish passage to the Buffalo River was blocked. An initial fish ladder was constructed in 1996 and an improved design was constructed in 2005, involving a 270-foot long fish ladder that would to allow fish to more easily bypass the 12-foot high Buffalo River Dam. In 2013, monitoring of the fish ladder shifted from assessing the effectiveness of the ladder in passing individual fish to assessing if and how the Buffalo River contributes to the Henry’s Fork fishery. PIT tagging to monitor movement of trout and genetics analysis to better understand their life history were underway. HFF also operates a fish trap from early February to mid-June each year to collect data on species, length, and sex before passing the fish upstream into the Buffalo River. This data allows us to quantify run size, run timing, number of spawners, number of return spawners, and other valuable information needed to monitor and understand the Henry’s Fork Rainbow Trout population.   The following are a summary of 4 key findings related to the Buffalo River Fish Ladder. To learn more about each, see

35th Anniversary — Lessons Learned. Part 2: Buffalo Fish Ladder2019-03-14T21:21:57+00:00

35th Anniversary — Lessons Learned. Part 1: Ranch Habitat

In honor of HFF’s 35th Anniversary, each week in March and April we will share significant findings or key facts we’ve learned about the river over the past 35 years. Get ready for a crash course in Henry’s Fork trout habitat, fish passage, macroinvertebrates, hydrology, Island Park Reservoir, water quality, economic value of fishing, and water management.   35th Anniversary -- Lessons Learned PART 1:  Ranch Habitat A great deal of research was conducted on fish habitat, especially in the Railroad Ranch reach, to answer the question “What limits the trout population and how can we increase it?”. Much of this research was conducted between the mid-1980s and late 1990s by graduate students of Dr. Jack Griffith of Idaho State University, with additional research conducted in 2013-2014 by graduate student Zach Kuzniar. What follows is a very simplified summary of five key findings related to Ranch habitat. To learn more about each topic or research effort, follow the links provided or visit us at the HFF Community Campus for additional resources.   1.  By the mid-1990s, research identified winter survival of juvenile rainbow trout as the single factor limiting the population in the reach from Island Park Dam to Hatchery Ford. (Gregory,

35th Anniversary — Lessons Learned. Part 1: Ranch Habitat2019-03-06T20:07:18+00:00

Water Supply Improves in January

January climate stats: 1 degree F above average temperature, 89% of average precipitation, and 83% of average snow water equivalent (SWE) accumulation. February 1 water-year totals: 85% of average precipitation and 77% of average SWE. February has better than even odds of being colder than average, and has started out very wet. Island Park Reservoir has been steady at 88-89% full for the past two months. Outflow has averaged 520 cfs. January wetter than December, but still dry The month of January was near average in temperature, at 1 degree F warmer. Although two periods of moderate to heavy precipitation occurred during the month, monthly precipitation was only 89% of average. New snow water equivalent (SWE) accumulation for the month was 83% of average. However, January was quite a bit wetter than December, so even these modest monthly values moved water-year totals up a little. Accumulated precipitation increased from 84% of average to 85% of average over the month, and SWE increased from 71% of average to 77% of average. Precipitation was not uniformly distributed across the watershed during January. Valley areas and the upper Henry’s Fork received a disproportionate share of precipitation. The upper Henry’s Fork subwatershed received 99%

Water Supply Improves in January2019-02-06T19:29:55+00:00
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