2021 Annual Ranch Report
Fishing was generally good throughout the summer and early fall. We had good Green Drakes on 15 June and they hatched daily, through 27 June. During the period, there were several mornings of fine dun fishing; however, it was surprising my clients and I had very few productive days fishing Green Drake spinners.
For me, the first good hatch of Flavs took place on 28 June, and we found them in excellent numbers on mornings that provided weather conducive to their hatching. The duns in the afternoons were complemented by good Flav spinner fishing on many mornings during the first three weeks of July.
We saw PMDs during June and early July, but there were few prolific hatches, particularly at the top and middle of the Ranch. The numbers of PMDs varied dramatically between sections of the Ranch. Lower water temperatures in some areas of the Harriman East, such as below Big Osborne Springs, provided better PMD fishing.
Flav and PMD spinners were excellent in July when flows from Island Park Reservoir were not too high and the weather was not too hot. (Unfortunately, we had temperatures in the 90s and flows as high as 1900 cfs during the period.)
We had excellent fishing with terrestrial dry flies throughout the summer. The high temperatures in early July resulted in the earliest hopper fishing I have ever experienced. My clients landed 3 fish on hoppers on 9 July, and we collectively landed 31 good rainbows during the month. I did not take the time to quantify how many fish we landed on hoppers in July in my other 38 years of fishing, but I am confident it was never more than five. (It is true that the 31 fish taken on hoppers in July represent a high percentage of the total of 52 rainbows taken on hoppers during the 2021 season. There is a personal reason for our not taking more rainbows on hoppers in August. I did not fish, or guide, for 11 consecutive days during the month because I spent the time with one of our daughters whom, as a function of COVID, I had not seen in 18 months.)
The fishing of hoppers continued to be good through the middle of September. Flying black ants were seen in good numbers early in the season and provided fine fishing into September.
Spinner fishing in the mornings and hopper fishing in the afternoons provided many productive days from the 20 of July though the second week of September. It is true that we had days when we did not land a rainbow, and a few when we failed to even hook a fish. High daily heat and water temperatures made it difficult to find rising rainbows on more than a few days.
Tricos appeared early in August and the spinners and duns provided excellent fishing from the middle of August into September. The Trico dun fishing was as good as I have had in any other year.
Unfortunately, we had very poor honey ant fishing, seeing them only on a few days and landing only one rainbow on honey ant imitations. It is relevant to add that honey ants were my third most productive fly in the first 29 years I fished and guided on the Harriman Ranch.
Mahogany duns also arrived early, about the 20th of August, and we had good, if not very challenging, fishing with them through the middle of September. One fascinating aspect of the Mahogany fishing was that most of the bugs were smaller than they have been in other years. In previous years, my standard sizes of Mahogany duns have been 14s or 16s, but in 2021 a size 18 imitation was often necessary.
I allocated 451 hours to fishing and guiding walk/wade trips during June, July, August, and September. My clients and I, and friends who fished with me when I was not guiding, landed 136 rainbows of 17 inches or longer. Every fish was taken on a dry fly. Twenty-five of the rainbows, or 18.3 percent, were 20 inches or longer in length. The 18.3 percent figure is comparable to 19.6 percent of rainbows of at least 20 inches or more in length my clients and I landed in 2019, and the 19.4 percent my friends and I took in 2020. What makes the three, highly comparable percentages of fish of at least 20 inches in length taken in the three years significant from the perspective of the status of our rainbow population, is that they are significantly lower than the 30 to 33 percent of the rainbows that were at least 20 inches in length taken in my previous thirty-six years of fishing and guiding.
The decline in the numbers of rainbows of 20 inches or more in length is not necessarily indicative of an inferior population. I suspect most fishery biologists would argue that the 30 to 33 percent figure we had for fish of at least 20 inches in length prior to 2019, 2020, and 2021 was indicative of a rainbow population that was “top heavy” in large, older fish.
Another intriguing comment concerning our rainbow population is that in 2019, 2020, and 2021, we, collectively, landed only one fish of 23 inches in length or longer. The one 23-inch rainbow contrasts dramatically with other years in which we landed many more rainbows of at least 23 inches in length. An impressive contrast is provided by the two, not three, years of 2010 and 2011 when my clients and I landed seven rainbows of at least 23 inches or longer. (For those who are not familiar with the Harriman Ranch, my comment “at least 23 inches in length” should not be interpreted to suggest we are taking multiple trout of 27 inches or longer on dry flies. The largest rainbow I, my clients, or friends have landed over my 39 years of fishing and guiding was a measured 24.5 inches in length—that is from a sample of 2,562 rainbows of 17 inches and longer, which includes 696 of 20 inches or longer. Despite taking almost 700 fish of at least 20 inches in length, only 28 attained a length of 23 inches.)
In 2021, the largest rainbow my clients or I landed was 22 inches in length. There were two fish that achieved that length. My photographs demonstrate that those 22-inch fish were heavy for their length. One measured a full five inches when the distance from the top of his back to the bottom of his belly was measured in a straight line.
While I found one fish with a gill pathology, the vast majority of our rainbows appeared to be in good health and fit. I did find one large, dead rainbow floating near the Hopper Bank. There was no evidence the fish had suffered from a physical injury or pathology. Obviously, it could have succumbed to a pathology I was incapable of defining, but I wonder if the over 90-degree heat of the day I found it, and the high heat on several preceding days, may have contributed to its demise. That is highly likely if an angler also played the fish for too long a period of time or took too many pictures of it after landing it.
My 2021 guiding was more productive than that of any previous year. I had 9 days when a client, or clients, took three rainbows of at least 17 inches in length. In my other 21 years of walk/wade guiding, my clients averaged 2.1 days per year of landing three good rainbows. It is shocking to me that my clients in 2021 produced more than four times the number of three fish in the net days than we averaged in any other year. I am confident the success of my clients was not because our fishing improved dramatically. That explanation is illogical because my own number of days of landing at least three fish of 17 inches or longer remained consistent with all my other years; in addition, several other Ranch regulars said their success was similar to previous years. I attribute the higher productivity of my clients to their special determination.
Variations in the Productivity of Flies Imitating Aquatic and Terrestrial Flies
We continued to see the decline in the productivity of dry flies imitating many species of aquatic insects. Unfortunately, the dramatic improvement in caddis fishing we experienced early in 2020 was not extended into 2021. My clients and I only landed one good fish on a caddis imitation in 2021—after landing eleven in 2020. I am confident the better caddis fishing we had in 2020 was not the beginning of a return to the superb caddis fishing we had in earlier years, but rather, a one-year aberration. (As my Table One below documents, caddis adult flies were my fourth most productive dry fly during the 1983-2011 period.)
We also took very few fish on PMDs. During the two years of 2020 and 2021 my clients, friends who fished with me, and I took a total of only five good rainbows on PMDs. To put that number in perspective, PMD dun imitations were my most productive dry fly in the period of 1983-2011. I shall concede that some anglers who spent many days below Big Osborne Springs on the Harriman East, had more good days with PMDs. I am confident the lower water temperatures in the area are the reason for the disparity in productivity of the PMDs. The reason I do not take many clients to the Harriman East is a function of the high number of walk/wade anglers who fish the area and the many skilled guides who float it in drift boats. I loved to fish the Harriman East in the 1980s, when on most days I would be the only angler and no boats, and I hate to impose my clients to the many anglers and boats they will encounter in the area today.
Another aquatic insect that has declined dramatically in recent years is the Callibaetis spinner. It was my seventh most productive fly in the 1983-2011 period, producing 105 rainbows. In 2021, we took no rainbows on Callibaetis spinners. Despite not taking a fish on Callibaetis spinners in 2001, it still ranked forth in production for the 2012-2021 period, producing no less than 7.4 percent of our rainbows. Is there a rational answer to the rapid, recent decline in the Callibaetis spinners?
A fascinating exception to the decline in productivity of fishing imitations of aquatic insects was seen with Flav duns and spinners. My clients and I landed no less than 18 good rainbows on Flav duns and spinners. Before you reject 18 fish as a modest number, reflect on how many fish my clients and I hooked on the Ranch to land the eighteen large rainbows. Clients land only approximately 30 percent of the mature rainbows they hook, and I land an average of less than 60 percent.
Our fishing in 2021 with terrestrial insect imitations was superb. We took 52 good rainbows on hoppers and landed 30 on black flying ants! Despite the high productivity of hoppers and flying black ants in 2021, we had poor fishing with honey ants and black beetles. In 2021, my clients, friends, and I landed only one fish on a honey ant and one on a black beetle.
I collected the data presented in the two tables below over the last 39 years, and it demonstrates that there has been a dramatic alteration in the productivity of dry flies that imitate aquatic insects as contrasted to those representing terrestrial insects.
The variations came to my attention when I began to compare the results of my fishing after my Ranch book was published in 2012. The data from the period, 1983—2011, contrasts dramatically with the second period of 2012—2021. The average time I spent fishing and or guiding on the Ranch each year was three months. I invested 14,314 hours fishing and guiding on the 8.5 miles of water during the 39 consecutive years.
Table One identifies the most productive dry flies for the period of 1983 though 2011. Table Two addresses the most productive flies for the period of 2012 through 2021. The numbers articulated for the good fish landed during the respective periods—1,523 in the first period and 1,079 in the second period, address all the fish taken during the periods that were at least 17 inches in length.
When I focus on the percentages of fish taken by the flies imitating aquatic as opposed to terrestrial insects in the respective period, I will use the sum of the rainbows produced by the six most successful flies on the two lists. That total for the six flies on the 1983-2011 list is 805 fish, and the sum for the six flies on the table for the second period is 616.
My clients and I do not fish streamers, leeches, or nymphs with indicators, or dropped under hoppers or other large dry flies. We do use the sight nymphing technique, but none of the nymphs we fished in that manner made either list of the most productive flies. Ninety-six percent of our 2,602 rainbows of at least 17 inches were taken on dry flies.
TABLE ONE: Six Most Productive Flies for the Period of 1983 through 2011:
1-Pale Morning Duns = 186 or 12.2% of all 1,523 rainbows taken between 1983 and 2011, and 186, or 23.1% of the 805 rainbows on this list of the six most productive flies used during the period.
2-Flav Duns = 137 or 17.0 % of all the 805 rainbows taken by the six most productive flies.
3-Honey Ants = 129 or 16.0 % of the 805 rainbows.
4-Caddis Adults = 125 or 15.5 % of the 805 rainbows.
5-Black Beetles = 115 or 14.3 % of the 805 rainbows.
6-Rusty Spinners = 113 of 14.0 % of the 805 rainbows.
TABLE TWO: Six Most Productive Flies for the Period of 2012 Through 2021:
1-Grasshoppers = 245 or 22.7 % of all 1,079 rainbows taken since 2011, and 245, or 39.7% of all the rainbows on this list, 616, of the six most productive used during the period.
2-Black Flying Ants = 121 or 19.6.% of the 616 rainbows on this list of the six most productive flies.
3-Flav Duns= 90 or 14.6% of all 616 rainbows.
4-Green Drake Duns=61 or 9.9% of all 616 rainbows.
5- Honey Ants=53 or 8.6 % of all 616 rainbows.
6-Callibaetis Spinners=46 or 7.4 % of all 616 rainbows
Comments on the Tables
Of the list of six most productive flies from the period of 1983 through 2011, four of the flies—PMD duns, caddis adults, rusty spinners, and black beetles did not make the list for the 2012-2021 period. The four flies that imitated aquatic insects: PMD duns, Flav duns, Caddis adults, and rusty spinners provided 561 fish, or 69.6 percent of all the fish, 805, taken by the six most productive flies used during the period. The two terrestrial flies on the list, the honey ant and black beetle provided 244 fish or 30.3 percent of all the rainbows, 805, taken by the six most productive flies.
There were four new flies on the six most productive fly list for 2012-2021. They include grasshoppers, black flying ants, Green Drake duns, and Callibaetis spinners. There were 197 rainbows, or 31.9 percent of the 616 fish on the 2012-2021 taken by the three aquatic flies on the 2012—2021 list: Flav duns, Callibaetis spinners, and Green Drake duns. Imitations of terrestrial insects, including hopers, honey ants, and flying black ants, took 419 rainbows, or 68.0 percent of the 616 rainbows in the second period, of 2012 through 2020. Essentially, the productivity of the flies imitating aquatic as opposed to terrestrial insects has been reversed between the two periods of my guiding and fishing!
It is difficult to imagine a more impressive alteration in the productivity of flies imitating aquatic as opposed to terrestrial insects in a period of thirty-nine years. It is my sincere belief that all those working to try to halt the deterioration of the Henry’s Fork fishery should aggressively be attempting to determine why the alteration in the productivity of the respective types of flies has been so dramatic.
Similar reductions in aquatic insects are being reported from many other rivers in America. In many areas, two types of insects, caddis and PMDs, seem to be particularly susceptible to whatever it is that is contributing to a general decline in aquatic insects. Many fishery biologists are suggesting climate change may be a major factor contributing to the precipitous decline.
Weather in 2021
As I have indicated, we experienced very hot weather during the summer of 2021. On more than a few days temperatures reached into the 90s. Not surprisingly, water temperatures on the Harriman Ranch were high when compared to temperatures in other years.
Fishing was impacted by the high-water temperatures. As I mentioned, one remarkable experience in the context of the unusual heat was I began to see hoppers on the water at the top of the Ranch as early as 6 July. As a function of the unusual heat, I began to take water temperatures three times a day, from late July until 14 September.
Most of my temperatures were taken between the Top of the Ranch and Osborne Bridge. There were two reasons for my spending most of my guiding time in the middle and top of the Ranch. First, I hate to encounter many anglers when guiding, and if a client is willing to walk at least 30 minutes from a parking area on the top or middle of the Ranch, we will dramatically reduce the number of anglers we will encounter. In addition, I wanted to take the temperatures in areas that were not directly below large springs, as is the case on many sections of the Harriman East.
What follows is a compilation of the average Fahrenheit water temperatures taken three times at day, between the hours I documented.
Late July: 8:30-9:30 AM=62, 12 noon-1:00 PM=65, 4:00 PM-5 PM=69.
Early Aug: 8:30 AM- 9:30 AM=63, 12 noon-1 PM=66, 4:00-5:00 PM= 69.
Mid- August: 8:30-AM-9 AM=61, 12 noon-1 PM =64, 4:00 PM-5:00 PM=67.
Late August: 8:30 AM-9:30 AM=56, 12 noon-1 PM=58, 4:00 PM-5;00 PM=61.
Early September: 8:30 AM-9:30 AM=53, 12 noon-1 PM=57, 4:00-5:00 PM =59
The highest water temperature I recorded was 71 degrees. That temperature was recorded at Osborne Bridge at 4:30 in the afternoon on 25 July. The 71-degree temperature was replicated one other time. The two 71-degree temperatures are very disturbing in the context of the health of the fishery.
Yes, I took much lower temperatures when I was near large springs on the Harriman East water. For example, on 11 September, I guided below Big Osborne Springs and the temperatures were 45 at 9 AM, 47 at 12 noon, and 50 at 5 PM.
The low temperatures do not contradict what was happening with the disturbingly high-water temperatures in most other sections of the Ranch that are not fed by nearby springs. In addition, I could have had much higher average temperatures if I had concentrated my collection of data from areas that were all significant distances from springs—for example near Osborne Bridge where I took my highest water temperature. I believe the areas I selected provided reasonable average temperature for the entire 8.5 miles of water. I suspect most fisheries biologists would be highly concerned about the 71-degree water temperature in flowing rainbow trout habitat.
Heavy Aquatic Vegetation
As my photographs indicate, we saw significant proliferation of aquatic vegetation in many sections of the Ranch in late July, August and early September. The shot of my client with one of his wading boots covered with heavy weeds was not staged. We were wading below the Big Island, when I got my feet caught in the vegetation, and I asked him to lift one of his feet for my photograph.
The vegetation not only makes wading difficult, but potentially dangerous. In 2021, I had a client fall in the water as a function of getting his feet caught in the vegetation, and I did it once. During the summer, a Ranch angler’s death was deemed to be from drowning. I do not know to what other health problems may have contributed to the tragedy, but it seems reasonable to suggest he could have had a stroke or heart attack before drowning, or he may have had other health “pre-conditions” that contributed to his death, but my many hours wading, suggests it is eminently possible the drowning could have been the result of the angler’s feet becoming entangled in dense aquatic vegetation.
The vegetation makes it much more difficult to land fish. In August, it is rare to not have large rainbows run through blocks of aquatic vegetation when you are playing them. Obviously, the heavy vegetation can not only result in your leader tippet breaking, but also the hook is more likely to pull out when pressure is put on it from a different angle as a result of a rainbow picking up a heavy block, or blocks, of vegetation on your line.
The Continued Decline in Our Native Whitefish
There was a continuation of the conspicuous decline in our native whitefish. They were seen in significant numbers on the Ranch water up until the early 1990s. Since 2012, my clients and I have landed 1,079 good rainbow trout and one whitefish. In contrast, in the 1980s there were so many whitefish that they would drive anglers crazy when they ate the flies they were casting to rising rainbows, particularly when Brown Drakes were hatching.
In conclusion, 2021 provided good fishing despite unusually high daily temperatures during the summer and early fall season; in addition, the vast majority of rainbows we landed were in good condition. The most disturbing findings of the summer was a continuing decline in many species of aquatic insects and high water-temperatures in many sections of the Ranch.
Timothy Craig Haley
Thank you for your amazing record keeping, thorough reports, and willingness to share this. I have been reading them for a number of years and find them very insightful. I live in nearby Bozeman, and have been dry fly fishing the Ranch for many years- 30-40 yrs. Your observations corelate with mine.
Thank you for taking the time to publish this information. Always a great and informative read. A productive year on the ranch but I definitely miss the PMD hatches of years gone by. Looking forward to June 15th.
I wrote the utah fish game about loss of insects on rivers,asked if they can do a study and figure out insect biomass per mile,to compare a river with mayflies to one without.I think upland bird chicks have been effected also by loss of insects and i think the problem is airborne.
Great article as always Johnno. Look forward to seeing you again in late June
Thank you John!
As always, incredible detail, insights and observations. John's annual recaps provide us all useful and confirming information. I'm certain a large number of annual visitors to Last Chance and Harriman have observed similar changes in the region's subtle adjustments to insect populations, in-stream plant growth, rising water temperatures and to some degree, a decrease in fish hooked and brought to the net. (of course, the dwindling numbers of fish brought to net could be caused by my steadily slower reflexes and growing lack of concentration). What John provides in his fastidious observations and record keeping only confirms what many anglers throughout the region are experiencing firsthand. An accelerated impact that climate change is delivering to local and global concerns. I do feel a deeply rooted guilt in driving my SUV and travel trailer the 2000 miles each way each way I annually travel in order to reach my Shangri-La.
Great article John, very informative and of interest.
Thanks, John. It's good to have access to such a comprehensive database for the Ranch. The angling statistics are interesting, but I'm more intrigued by your views on the insects and your temperature measurements. A couple of questions. What year was the dam redone and the bladder installed so that the most, if not all, the water out of the reservoir was coming off the bottom of the dam? And what changes in insect emergences and abundance did you catalog after the change to the dam? All my guiding on the Henry's Fork was before the dam was altered, but it's always seemed to me that there was a pretty major shift afterwards. My question now is whether an increase from cold water off the bottom of the dam is being neutralized by hotter air temps and warmer water temps ...
John, were the water temperature readings taken at the same locations from day to day?