Claim: For trout fishermen, climate change will mean more driving time, less angling

Looks like a hilarious positive feedback loop, more driving, more emissions, less trout, more driving…

This is an eastern brook trout. CREDIT: Penn State
This is an eastern brook trout. CREDIT: Penn State

From PENN STATE

When trying to explain the potential effects of climate change on plants, fish and wildlife, scientists usually resort to language that fails to convey the impact of warming. Now, a study by Penn State’s College of Agricultural Sciences fisheries researchers clearly explains the impact of projected warming waters on wild brook trout in the eastern U.S. for fishermen.

The eastern brook trout is a socially and economically important fish that occurs in small cold water streams and lakes, and self-sustaining populations support angling throughout the Appalachian Mountains, from Maine to Georgia. However, warming air temperatures are expected to reduce available cold-water habitat and result in a smaller brook trout distribution and fewer angling opportunities.

Building on recent research at Penn State, Tyler Wagner, adjunct professor of fisheries and Tyrell DeWeber, now a postdoctoral scholar at Oregon State University, used two models they previously developed, one predicting stream temperature and one predicting where brook trout might occur, to identify streams likely to support wild brook trout under current and future climate scenarios.

The researchers then calculated the distance required to drive from the centers of 23 cities spread throughout the eastern brook trout range to the 10 nearest stream segments likely to have wild brook trout under current and future conditions. They published their study in a recent issue of Fisheries.

“Climate change is expected to result in widespread changes in species distributions for freshwater fish species. Although anglers and other resource users could be greatly affected by these predicted changes, changes are rarely reported in ways that can be easily understood by the general public,” said Wagner, who is assistant unit leader of the Pennsylvania Cooperative Fish and Wildlife Research Unit at Penn State.

The effects of climate change on fish and wildlife are usually reported to the general public using summary metrics or maps designed to communicate concepts that are not normally encountered in everyday life, including changes in habitat suitability, range shifts, or increasing risks from disease or extreme events, according to Wagner. “Though these metrics are necessary, meaningful, and understood by scientists, many people lack the necessary training and background to readily understand them.”

“Further, scientists and nonscientists alike may struggle to convert these metrics into a currency that directly affects day-to-day life. Climate science is a complex issue, and when we communicate potential responses of vegetation, fish and wildlife to nonscientists, creative thinking with respect to the currency of communication will facilitate discussions between scientists, policy makers and the public.”

DeWeber, who was a doctoral student at Penn State when the research was conducted, noted that travel costs based on distance have been widely used to value ecosystem services such as angling under climate-change scenarios, but have not been used for communicating potential changes to the public, despite the intrinsic link to everyday life.

“Under current conditions, brook trout are predicted to occur in streams throughout the region, and average driving distances from cities to the nearest streams predicted to offer angling opportunities ranged from 4 to 87 miles. As a result of projected warming, driving distance to go fishing for wild brook trout was predicted to increase, on average, by almost 164 miles over the next 70 to 80 years.”

For example, the driving route from Philadelphia to the nearest brook trout stream was predicted to cover 249 miles in a warmer future, much longer than the current 48 miles.

The lengths of trips from many northern cities, such as Bangor, Maine, were predicted to increase but were still relatively short in the future because nearby streams were still predicted to support brook trout under warmer conditions.

In contrast, anglers in southern cities, such as Cleveland, Tennessee, would experience dramatic increases in the lengths of trips because brook trout are predicted to be lost in surrounding areas.

Although anglers tend to be very dedicated, DeWeber pointed out, it is unlikely that many would drive great distances to fish very often due to cost, especially if those last remaining streams become popular and crowded. He believes that losses of wild brook trout populations and increased trip lengths would likely result in reduced resource use in many areas.

But he suggested that people are unlikely to be concerned about the potential effects of warming if they do not understand what may be coming. “Communicating species responses to climate change in everyday language could greatly increase the ability of resource users and other members of the general public to understand and relate to predicted changes,” he said. “A clear understanding of potential changes might not lead to greater societal concern about species’ responses, but it may enable people to make informed decisions.”

###

The U.S. Geological Survey, National Climate Change and the Wildlife Science Center supported this research.

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carbon bigfoot
August 21, 2015 4:44 pm

If the brook trout is such an endangered species then why is it the PA Fish & Boat Commission never raises or stocks them? Its because they are only native to spring fed steams and those are small streams, accessible to only the die hard fisher guys and girls. Only Brown and Rainbow are raised and stocked because they are more resilient to tempered waters which are more accessible to most PA fisherman and the waters that are stocked. Once in a while they stock an occasional cutthroat trout— not an indigenous species to Pennsylvania.
Who ever suggested this study should be fired.

Laurie
Reply to  carbon bigfoot
August 22, 2015 11:34 am

58 years ago, I caught my first brook trout in the dead of summer from a tiny stream running through a meadow. I have pictures. The pool was probably 3 feet deep at the upper end and 6″ at the other end. When the waters are low and the weather is warm, trout go to the deepest part of a pool or an overhang of embankment or boulder. These are also good blinds when they are hunting, (not feeding… they hunt their meals). Over the years, I fished these streams in summer and winter. They did well under ice (smaller servings of bait, please) and on hot summer days (early morning or dusk, please). Wild trout are hearty. Brook trout have more “slime” over their scales in warmer water. It’s protective. I used to get a laugh when campers in the camp ground, who made comments as I passed with my rod in the morning, would be so surprised that the little creek would have such nice fish in it. Hot years, cold years… the brook trout remained. Here are the real dangers to trout: Oxygen sucking algae blooms mostly from nitrogen run offs from cattle grazing and developers, (but trout move upstream to escape), fish kills to remove better adapted and predatory fish, such as the brown trout, in order to save the native golden trout in CA, who get Xs for eyes as soon as a fisherman approaches the bank, diseases from hatcheries such as whirling disease in CO, heavy equipment damage from logging, (although the fish recover quickly) and catch and release anglers. (My wildlife biologist friends tell me that 60% of fish die after being released.) Another problem for trout plants: STUPID people who plant trout from a 60 degree container into a 70 degree lake or river. Even a small child will learn this will shock a fish and kill it. I’ve seen thousands of fish poured into the lake downstream from my CA home on the river, only to immediately go belly up. As for the fans of artificial lures and flies, what an unfair situation for the fish. Why not offer something good for the fish to eat? I like grubs and crickets earlier in the year and cheese or worms later. Use a barbless hook. This way, if the fish gets away, he gets a meal. If he doesn’t, you get a meal. Don’t like to eat trout? Why the *&)^* do you fish? Call me “die hard fisher girl who loves her heart healthy trout.”

Albert Paquette
August 21, 2015 4:55 pm

Dear Ty and Ty: Thank you for dumbing down the results of your fish study so that I could understand it. I was getting confused right at the outset when you started using words like “model”. I couldn’t figure out the connection with the fashion industry, but you cleared things up quite nicely for me and I presume for most of the scientifically illiterate unwashed masses.

Reply to  Albert Paquette
August 22, 2015 5:22 am

+10

David M
August 21, 2015 5:06 pm

I figure that is the time sea level is going to rise…thus pushing the fish back inland

August 21, 2015 5:09 pm

I seem to recall a book of poems “trout fishing in America” by a guy that was at least passionate about trouser trout!

Rattus Norvegicus
August 21, 2015 5:15 pm

This isn’t conjecture. I live in the heart of some of the best trout fishing in the US and we have started to have stream closures (“hoot own” closures) in the afternoons on streams in these parts every summer. This has not been the case in the past. It is a fact of trout biology that they get stressed when water temps get much above 60F and that being subject to the stress of being caught (and released, of course) is bad for their mortality. So even here in the heart of trout country warmer streams mean a drive up into the mountains to the headwaters if you want to fish after work.

Bubba Cow
Reply to  Rattus Norvegicus
August 21, 2015 6:40 pm

so where is this heart or trout country – can you cast to the Madison?

Ockham
Reply to  Rattus Norvegicus
August 21, 2015 9:34 pm

A deceptive statement indeed. I’ve lived and fished in Montana for over 30 years. Low flows and warm summer water temperatures are no stranger to our streams and rivers. Summertime restrictions and closures that “have not been the case in the past”, are more a function of an unprecedented increase in angling pressure in recent years than anything else.

Reply to  Rattus Norvegicus
August 21, 2015 10:07 pm

Just how many of these stream closures are around? Just one ratty?
And was that the ‘sole’ reason for closing the waters, or were the local eco-devout so devout that they closed the streams because of belief?

Reply to  Rattus Norvegicus
August 21, 2015 10:47 pm

… we have started to have stream closures …
We have them, too. They closed the Animas River to protect the stressed out orange trout.

Laurie
Reply to  Colorado Wellington
August 22, 2015 1:06 pm

Orange trout HAHAHAHAHAHA! Scientific name:EPAorangicleleadarsenicbellyae

Taphonomic
August 21, 2015 5:16 pm

Some of the best trout fishing can be found from cold water releases below dams (e.g., San Juan River below the Navajo Dam). So as a simple solution: more dams. But then, these predictions discussed in this article are based on climate models that can’t replicate the pause, so no apparent need to worry.

August 21, 2015 5:18 pm

The lengths of trips from many northern cities, such as Bangor, Maine, were predicted to increase
***************************************************************
bull
penobscot river (brook trout and landlocked slamon) runs right between bangor and brewer maine (it literally is the boundary) and is only a 10-15 minute drive from anywhere in bangor/brewer to the river.
I’m about 30 minutes away (at 85 mph) but the river is not going to veer direction and change distance.
there are a ton of fresh water lakes, ponds and streams here too.

August 21, 2015 5:49 pm

It’s worse than we thought. You may have to go the Australia for the last bit of trout fishing – but it’s going to be a little crowded:

hunter
Reply to  J. Philip Peterson
August 21, 2015 7:57 pm

Great reference! +10. An apocalyptic movie about the past end of the world scare to illustrate just how little changes in the promotion of apocalyptic claptrap.

Reply to  hunter
August 21, 2015 8:39 pm

For some reason (I saw this in a theater when it came out) I remembered the trout fishing scene. I trout fished in north central PA for many years. Sometimes on opening day on Kettle creek it was almost as crowded as the scene in this movie…I wonder what the stream temps are now compared to 1960s-70s…

George Devries Klein hD, PG, FGSA
August 21, 2015 5:53 pm

I guess the message is, GO NORTH if you believe this Caribbean Research Atoll Project (Acronym is – you can figure it out)

David Walton
August 21, 2015 5:55 pm

Penn State academics should be ashamed of themselves, but they are not. This is a pernicious and destructive illness that pervades all academia.

Reply to  David Walton
August 22, 2015 4:04 am

Yes indeed. All of academia.
The educational establishment is far worse than even the freaks involved in “climate science”.

Sweet Old Bob
August 21, 2015 6:05 pm

Looks like the trout are mostly limited by that acidifing sea water….Georgia must be as cold as Maine…/sarc … Who knew ?

August 21, 2015 6:12 pm

So let’s get this straight…
The temperature rises worldwide and CO2 follows, worldwide.
So the CO2 causes glacier retreat because they retreated worldwide.
The lunatics run the nuthouse.
And BTW: whoever thought that with over 6 bil people on the planet, we can all go out living the lifestyles of hunter-gatherers? That’s fantasy land stuff all by itself.

David Chappell
Reply to  Ron House
August 21, 2015 11:51 pm

Well, no. They want to keep a few peons to do the hunting/gathering for them and get rid of the rest of us.

eyesonu
August 21, 2015 6:24 pm

I don’t have time to make a reasonable response at this time. In Virginia the DGIF (Department of Game and Inland Fisheries) and their Virginia Wildlife Magazine are rife with CAGW. The editor of the Virginia Wildlife Magazine , Sally Fields, supports and publishes any CAGW articles sent in by a very few contributors. I stopped my subscription years ago after probably 35 – 40 years. I would be glad to list the authors of the articles. It’s much worse that you thought.
I was catching more trout than I ever caught while the VWM pitched a loss of trout.
I no longer have a subscription after 30+ years. I am trying to no longer support the DGIF while she is on board.
Not much I can do but I’m doing all I can. She’s got more holes than Hillery. A once great organization driven into the mud. Very sad

Reply to  eyesonu
August 21, 2015 7:47 pm

Subscribe to Wisconsin DNR. Bi monthly. Lots of good stuff about waterfowl, turkey, deer, bear, and such (fish). No CAGW. I own a fairly large farm in SW Wisconsin where all that stuff has been personally proofed out. After about 30 years of experience, WDNR is about right. (On most stuff, not all–I favor wolfs, they do not. I favor trapping coons to facilitate ruffed grouse, they do not…). Beats the ‘hey’ out of anything else. Whether you are for or against wolves and raccoons.
BTW all, the most exciting thing on my farm two years ago was a wolf family (probably just coy wolves, essay No Bodies) that set up for a summer/fall in one of my pastures. Got many trail pics.
And, in the deeper woods trails, trail cams also got a family of lynx going down my logging roads. Man, my efforts to restore the farm’s natural wilderness zones are paying some dividends. I will (ineptly) endeavor to somehow eventually attach the lynx family trail photos here.

eyesonu
Reply to  eyesonu
August 22, 2015 3:12 am

I need to correct an error in my above comment. The editor of the Virginia Wildlife magazine is Sally Mills (not Sally Fields).

Charlie
August 21, 2015 6:26 pm

Tout Fishing is too hard as it is. So of course people might as well make it harder and try to catch one on a fly rod. I don’t know if trout fishing was ever actually about catching trout. i will stick to my ocean fishing.

Reply to  Charlie
August 21, 2015 7:58 pm

Charlie, trout fly fishing is the ultimate sublime. Been doing it since a small kid, including tying own flies (heck could not afford it otherwise then). Seconded only to fly fishing small mouth bass tail walkers in larger streams/ lakes like in northern NE and Southern Canada. You salt water guys just do not know what true heavenly fishing is… not pounds per fish, just fight per ounce… (aw, OK, I now live on the FLL ocean and reef fish there too… but maintain my lifelong cold freshwater bias.)
Regards to any and all true fishermen. Willis, that means to you, too.

Reply to  ristvan
August 21, 2015 11:55 pm

Fishing is sublime.
Trout are just one of the diversionary streams of fishing. I like trout fishing because fishing for them involves shade and cool air.
I learned to fly fish in Pennsylvania, therefore I thought overhead casting was just for distance. (Tree crowded streams cause most Pennsylvania fly fishers to learn to cast sideways to keep the fly out of branches.)
Gulf of Mexico fishing is wonderful, but one must be hot and sweaty while fishing the Gulf. That and determined to get beaten up by frequent thunderstorms. It is amazing how a storm forms overhead from previously clear air into a towering lightning emitter within a few minutes. One also quickly realizes just how small one’s boat is at the same time.
But the fishing is amazing; tuna, Spanish mackerel, bonita, king mackerel, red drum, flounder, snapper, amberjack, dolphin fish, speckled trout, cobia, etc…
The speckled trout common to Gulf of Mexico is also found along the Atlantic coast up to about Maryland; prefers warmer temperature. Named because of a passing resemblance to salmonids, speckled trout are actually a member of the weakfish (Cynoscion nebulosus) family an extension of the extensive drum family.
Speckled trout respond to fly fishing, even dry fly fishing. If one wants cool air, al one has to do is go speckled trout fishing during winter time; though very cold fronts cause speckled trout to go dormant. Extremely cold fronts can cause significant fish kills setting local fish populations back for years.
I like fishing for many different types of fish almost anywhere there is water. I’ve yet to see man made CO2 cause any problems to any of the fish or aquatic critters.

Pamela Gray
Reply to  ristvan
August 22, 2015 10:57 am

Bait casting methods (with a bait reel, not a baled reel) is the only way to go on complicated tree and brush-lined mountain streams. If the best hole is across the river with an overhang and you can’t get to it by crossing the river, you have to use a bait casting method to get your baited hook anywhere near that hole. A fly reel will catch trees, not fish, and a baled reel tends to snap your cast back at you when it hits the end of the line as you flip the bale back. Bait casting is the only way to go.
That said, one of these days I would like to learn how to fly fish.

Bubba Cow
Reply to  ristvan
August 22, 2015 11:12 am

bait vs fly – (actually being on/in the stream is the best)
http://www.theriverwhy.com/

Pamela Gray
Reply to  ristvan
August 22, 2015 6:19 pm

I just watched that movie (free youtube). Cried my eyes out. Hit very close to home.

Reply to  ristvan
August 22, 2015 7:42 pm

Pamela:
Accurate casting is best at all times.
Oddly, the seemingly clumsy fly rod is more accurate for many situations than bait or spinning rods. To insure pin point under cover accuracy with both bait and spin requires a fast rifle like cast as any arcing cast can only reach into the edges of cover.
Fly fishing, the line provides the required weight that flexes the rod. Using the rod to send the fly line loop that powers the fly and line allows a sidewise cast that literally casts the fly easily deep under branches yet lands it softly.
In small tight brushy cover with minimal rod room (forget casting), a fly rod allows a bow shot where the fisherperson aims and shoots the fly much like a person shoots a sling shot or bow and arrow.
Spinning rods are almost as good at this cast, but fast tapers make bending the rod risky for fingers and their large guides love getting hung up on braches. Plus their annoying method of ballooning line off of the spool increased chances of brush interaction.
Spin and bait casters often have to play the swing and drop method of casting. Easy to try, hard to master and noisy as all get out when that hook gear hits a small water surface.
In the same situation, fly fishers can reach out and using the length of the rod, dance the fly on the water surface; a technique known as dapping. A technique that would have been known to Dame Juliana Berners.
Tenkara fishing uses similar techniques.
Tenkara always me of cane pole fishing with the cane, line and hook, only the cane doesn’t collapse. Still one of the best methods for bluegill and crappie fishing.
Fly casting is actually easier for ladies. That baseball elbow that prevents women from properly throwing a fast ball goes a long way towards proper fly casting. Meanwhile those fast ball throwers have to work at preventing their wrists from snapping over. Ever see those dreadful pics of alleged fly casters whipping the water in front and in back of them? They’re definitely not fly casting, but I bet they can throw a fast ball.
Any time you’re passing through Virginia, or if I, for some silly reason pass up spending time in the Nevada and Utah deserts, and instead decide to addict myself with steelhead fishing up in the great Northwest, I would be happy to introduce you and your guy to casting a fly. As would, I suspect, quite a few other WUWT denizens. I do not promise success at catching or casting…
Sometimes a healthy gob of salmon eggs just beats the smack out of trying to convince fish that a feather and fur coated hook is tastier.

Bubba Cow
Reply to  ristvan
August 23, 2015 2:54 am

truth is – we need to go fishing by however method
sorry Pamela that movie was so emotional, but glad you enjoyed …

Pamela Gray
Reply to  ristvan
August 23, 2015 12:42 pm

ATheoK, you might be thinking of a different kind of river than what I fish in. There are probably only 3 places along the stretch of the river I fish in or its feedins that you can fly fish and the best one is all throw back. The other two have clearance but with the light test line of a fly rod and the size of fish that will bite, you will have to jump in or else the line will be snapped in two. Not a good idea to jump in. Dangerous snags in swift water are everywhere. And the river that is throw back? Water as cold as ice, cold enough to suck in arms and legs let alone, er..other parts. That particular bend in the river is at Williams Campground and we all used to swim there. You can still see the outline of the diving board that has rotted off its mooring and now sits at the bottom of a deep emerald pool.
Here it is in the Spring filled with runoff. Around the corner to the upper right is where the hole is and what used to be our diving board. Once the runoff slows down, the pool back there is perfect for fly fishing. But be careful. The shore is thick with snags shoved there by the current so you have to be careful not to cast too far. This photo is not mine but I have some very similar to it.
http://www.panoramio.com/photo_explorer#view=photo&position=12&with_photo_id=109129338&order=date_desc&user=63430

john
August 21, 2015 7:02 pm

Just so happens I’m gonna be catching some of those on my fly rod in Maine next week 😉

August 21, 2015 7:12 pm

Well, got here rather late. Within 15 miles of my Wi farm we have 4 class four trout streams. All infested with browns, originally just brookies. So this might be welcome. Meanwhile, I will just fly fish for both…

hunter
August 21, 2015 7:55 pm

An adjunct professor working on spinning tales to scare fishermen into believing apocalyptic claptrap.
By the way: I challenge anyone to offer an objective definition of “climate change” that is not self-referential of subjective.

Dog
August 21, 2015 8:21 pm

So at this point I can blame Climate Change© for if I get a flat tire on my way to go fishing – right?

August 21, 2015 8:30 pm

Growing up in Southern Michigan in the 1950s, I would ride my bicycle (and later my motor scooter) 18 miles north to a small creek that held a long term native population of brook trout. Where most of the trout actually lived was inaccessible, as much of the creek was overgrown with brush. But on one trip I managed to snag a 14.5″ brookie that really made my day (and a very tasty meal).
In the mid 1960’s, as local housing developments sprung up, the creek was “improved” for public recreation. A dam was built to create a small lake for swimming and more accessible fishing.
Result: warmer water. Bye bye brookies.
In the early 1970s, upper Peppermint Creek, a tributary of California’s Kern River, held a unique subspecies of rainbow trout, an intermediate species between the higher altitude golden trout and lower elevation rainbows. They were small, and easily spooked. Hard to catch, and not many tried.
An RV camping area was built along the creek, and the California DFG (yes, the same organization that spends $millions poisoning water supplies to remove “invasive species”) began stocking tons of hatchery rainbows to please the campers.
Result: Overcompetition for limited resources. Bye bye natives.
I’d like to see how many native fish habitats would still exist if government agencies hadn’t destroyed them.

Laurie
Reply to  verdeviewer
August 22, 2015 2:34 pm

verdeviewer, I started fishing upper peppermint when I was 7 (1958). It’s rugged! I last fished it in 2003 on a trip home from CO. As a child, we stayed at Quaking Aspen and often walked to peppermint. It’s a long walk but worth the trouble. It got easier once they built the highway. When I last fished there, it was still listed as a primitive campsite although they had put in latrines. To get RVs in there would have been a nightmare. They had to do a lot of tree removal and grading, I’m sure. When I lived on the Tule River (9 years), a group of us went to do rehab on lower peppermint, a much flatter and safer area. We planted willows mostly, to hold the banks and give more shade over the creek. I don’t know if it was really necessary but a neighbor committed us to do it. It was okay. I’m with you on the poisoning projects. What idiocy!

Brian S
August 21, 2015 9:19 pm

“Under current conditions, brook trout are predicted to occur in streams throughout the region, and average driving distances from cities to the nearest streams predicted to offer angling opportunities ranged from 4 to 87 miles.” So it seems that they are uncertain about where the fish DO occur and how far away that might be even now but they for sure know that they won’t be there in future! I would have thought there should be a greater degree of certainty about ‘predicting’ the present.

Gamecock
Reply to  Brian S
August 22, 2015 4:02 am

Fishermen have been trying to find the fish since time immemorial. Now, if they can’t find them, it’s because of global warming.
Add it to The List.

August 21, 2015 10:14 pm

Are eastern brook trout
The new polar bears,
Saying their endangered
To stoke up our fears?
http://rhymeafterrhyme.net/the-time-has-come-to-stop-being-afraid/

DesertYote
August 21, 2015 10:44 pm

Of all the factors governing the range of any species of fish, temperature is least important. For trout, structure, competition, and nitrate levels are far more important. Brook trout are quite adaptable and sometimes become a problem were introduced. Now if stream temps are going to raise by greater than 8C I might be concerned.

asybot
August 21, 2015 11:05 pm

“As a result of projected warming, driving distance to go fishing for wild brook trout was predicted to increase, on average, by almost 164 miles over the next 70 to 80 years.”
Sorry I did not even read the comments. As usual there will be no-one around to verify any of this Cr.P. How can I get on this gravy train? Oh so sorry I don’t want to be on it . I don’t get travel sickness ever,
but this train makes me ill.

August 21, 2015 11:16 pm

“…For example, the driving route from Philadelphia to the nearest brook trout stream was predicted to cover 249 miles in a warmer future, much longer than the current 48 miles…”

Odd, the Wissahickon creek runs right through Fairmount Park in Philadelphia. And one can, as I have, caught trout right down to the creek’s intersection at the Schuylkill River, (at a deep pool that looks perfect for bass, bream and occasional muskellunge).
Yes, the Wissahickon creek is stocked, as are almost all trout waters that are located in high population urban areas. Yet trout still manage to have native populations.
Any direction North, West, or Northwest will quickly bring drivers, cyclers and walkers to more streams with trout in them.
Yet, 249 miles is a quite a trip from Philadelphia, almost to Canada on a Northwest track, well up into New York heading North, almost to Ohio due West and deep into West Virginia to the Southeast.
What happened to the limestone creek geologic area that begins within a hundred miles to the West from Philadelphia? Limestone creek waters issue from underground stream sources, are not dependent on air temperature and minimally affected by rainfall.
Limestone creek water temperatures are quite stable through the length of the limestone creek run, even on winter coldest or hottest summer days. A truly amazing site is visiting a limestone creek at dawn during severe cold fronts, as water condensation from the warmer stream freezes as hoarfrost on nearby trees and vertical objects. I suspect that similar early morning views can be found at hot springs nationwide.
Golf Courses and malls can hammer limestone creek flows by draining aquifers watering grass and landscaping.
Limestone creek/river is a description for when underground waters surface, even for brief periods of time. Many of these waters return underground while others merge into streams or rivers.
What is not covered by that description are the rather common underground water exits into larger drainage waters, e.g. seeps, cold springs, etc. Quite a few of these sources run as small cold streams before entering the larger waters.
All of these water outlets bring trout compatible water sources into even warm water flows. Trout will stay in or near bottom water eddies or under ground overhangs at stream edges.
The air may be hot, but generally these waters are cool, even cold from their interface with the Earth. Trout inhabiting these areas are not only minimally stresses but often active during the hottest summer periods. As they are ‘holdovers’ or even stream bred trout, they tend to be larger heavier trout. (hint, a local stonefly nymph drifted by or better under these overhangs can be productive.
A major factor on small stream water temperatures during summer is the amount of shade present. Expansive sunny areas of shallow water are easily warmed by sunlight. These same areas when shaded stay cooler. So much so that shaded shallow streams in extremely sunny Utah not only stay cool enough for trout, but also cool the air for quite a distance near the stream.
Not only a bogus modeled study, but a truly ‘Mad Max’ modeled eco-nut false fantasy. This sure seems to be a week for confirmation extremely biased research.

Larry Wirth
August 21, 2015 11:18 pm

Lived on Oak Creek (Sedona, AZ) in 1954-57 catching rainbows every day. Mom said we must eat everything we caught, so fried rainbow at least 5 nights per week. The local moms put out that for kids under 16, the limit was 5 per day, otherwise we would have brought home the actual legal limit of 10.
Other rule, clean them yourselves! So, at a time when my parents had little money we survived by the effort of children, including myself. Of course we also swam in the creek and had occasion to notice the other denizens. Most common were what we called “suckers”, probably a type of carp, algae feeders, which nobody ever suggested eating. There were, in our favorite swimming section, two (and only two) bass of unidentified species present, and 1000yds downstream in a much deeper pool, there were a few bluegills of unknown species.
How many of our current generation of children will ever have an experience even remotely like mine?