Study shows precipitous decline in population of adult rainbow trout in Bow River

[SkwalaStonefly]

Study shows precipitous decline in population of adult rainbow trout in Bow River

 

Trend could jeopardize Calgary’s world-famous recreational fishery, University of Calgary scientists say

 

See https://www.ucalgary.ca/utoday/issue/2018-11-26/study-shows-precipitous-decline-population-adult-rainbow-trout-bow-river

[Sparkplug]

 

I don't fish the Bow much, and thus there are others on this Forum who know it way better than I, but from following the threads here post-2013 flood, it seems to me that there has been much mention of relatively fat, healthy browns in the Bow, and more long, skinny rainbows.

I read somewhere years ago that browns are more tolerant of higher water temperatures and pollutants/contaminants in the water than rainbows.  Has there been any long-term tracking of these variables, alongside the flow rate monitoring?

The article on the aforementioned study pretty quickly goes to angling pressure as a contributing factor.  While no doubt this is a contributor, it would be nice to see acknowledgement of other changes in the river as well.  For example, the monstrous Enmax Shepard combined cycle power plant came on line a few years ago, and uses treated wastewater from the Bonnybrook treatment plant as its cooling water supply (water that would otherwise be discharged into the river).  And then there's my personal favorite, TransAlta's ongoing screwing with river flows to maximize upstream hydro profitability in Alberta's volatile power pool (wait until their PPA's expire in the 2020-2021 time frame, and then we'll REALLY see screwing around with the flows)...and on and on it goes.

One more (perhaps) obscure one:  I saw an article a while back that talked about the impact of forest fire smoke on emergent insects.  Can't have been a good couple of past summers on that front...

 

 

[TroutPanther]

Good points sparkplug. Pretty sobering report nonetheless.

We had a couple really good years for big rainbows, in 15 and 16 I think? This summer there seemed to be more snakey ones, but my anecdotal experience has been that the browns were almost unicorn status in 13 but have come back a fair bit.

Definitely lots of non-fishing issues at play here. Those flow fluctuations and low flows in mid summer after spring flood mitigation have been crazy. Certainly something needs to be done there, and great to see bow river trout advocating for these issues on behalf of the community.

The article mentions a lottery system - I really hate the idea. I’d much rather see a classified system implemented with the money going back into the resource, perhaps spring & late fall closures implemented during the spawn (apparently insta stars can’t help but to hammer spawners), barbless hook requirements, and mandatory closures when water temps cross a predetermined “unsafe to fish” level in the dog days of summer. Given they just changed the regs, I’m not counting on them doing anything any time soon. 

[ÜberFly]

Im not sure why the consistent Transalta  flow fluctuations weren’t address ( or commented on) in the article!! That’s a MAJOR factor for sure!!

[Sparkplug]

 

I haven't read the report itself, and perhaps there is more discussion/analysis of these other factors in there.  But the article certainly seemed to suggest a focus on angling as the major factor.

Maybe TransAlta funded the research project...

 

 

[bcubed]

The actual report states that there are many factors at play, and just mentions that managing angling impacts is the easiest to address. Which in this case, it is. That being said, it doesnt specifically call out transalta

[bcubed]

For those that want to read the report rather then the press release, BRT has it on their site:

 

https://bowrivertrout.files.wordpress.com/2018/08/cahilletal-2018.pdf

 

[trailhead]

Well I can't claim to be an accurate sample point but all the rainbows I got on the Bow this year were 20 inches plus and fat. Now I only got three but then I only fished the Bow four times. Mind you I caught four rainbows on the Elbow in town and they were all around 10 inches, but also fat and healthy.

[monger]

The study is based on historical F&W data collected in-house or via consultants. Over the years the sampling methods/areas/timing have been anything but standardized. In order to make sense of the available data, it was quite heavily massaged with some pretty complex statistical math. There are a large number of factors that can influence the river's productivity and population counts. A couple of major floods had very serious consequences in the short term, but the system seems to be able to rebound over time. There have been times when there was less fish around and times when the fishes' condition factors have been below what we normally expect. At present,  things seem to be on the poor end of the scale (especially the rainbows).  One thing about this study that I see as a blinking light.....there needs to be a standardized system established for collecting data so that we can compare numbers over years without creating fudge factors. Experimental design is a very valuable exercise before you even leave the desk to grab your electroshocker.

So many complex things to consider, very few of which we may even be able to control. One thing that is easier to measure is the number of anglers and angler effort. The angler population has really exploded over time, and the average skill level is probably increasing as well. This angler effort is one thing the government can attempt to control.

If angler effort is something they want to control, then the government needs to pay special attention to a subset in the angler population that is having the most impact in the fish handling arena....namely the guiding industry. Day after day pounding the water, skilled folks are putting a lot of pressure on this "threatened" resource. If the government wants to limit anglers and their impact, they better shine a bright light on the guiding industry before they start limiting access to Joe Public. Just a thought. 

[Tinyfly]

7 hours ago, ÜberFly said:

Im not sure why the consistent Transalta  flow fluctuations weren’t address ( or commented on) in the article!! That’s a MAJOR factor for sure!!

Absolutely, major omission that has huge impact on habitat and stress.  Only fished the bow for past 3 years but fished very same holes last summer with great success this year with very  little success.  You can’t tell me that’s mainly due to a year over year increase in angling pressure I think that’s way further down the list of contributing factors.

[1961flyman]

I feel that the study is somewhat myopic.

However, I also feel that the old data was wildly optimistic.

4,200 Trout per Mile ??    Bullshit..

It used to be advertised on Country Pleasures Brochures, Pre Dating Internet..

Wonder where that Data came from..

I feel that our Bow is going Downhill, FAST..

I believe Whirling Disease has been here for over a Decade.

I believe that Trans Alta is Hugely responsible.. Spin the Dams Up For Profit,, I have never scene the Bow at 52 CMS IN September  until this year.To Hell with any environmental Considerations.

I feel That Fishing pressure is  A Main Factor..  I have never witnessed the pressure of 2018..

As far as The Guiding question...Might be a good time to cap the number of Rod/Boat Days and totally Shut Off BC and Montana Guides..

I have Fished the Bow in the 60s.70s.80s,90s.2000s and the 2010s..

I know that Single Hook, Barbless and Seasonal Closures would Help, Immensely..

Very Complicated Issue and no EASY Answers...

[Dangus]

Add in a San Juan worm ban. 

Id like to see single barbless for nymph rig or barbless dry/dropper.  

Social media is to blame. 

It has only been a season or two for catch and release.  

[TroutPanther]

1 hour ago, monger said:

The study is based on historical F&W data collected in-house or via consultants. Over the years the sampling methods/areas/timing have been anything but standardized. In order to make sense of the available data, it was quite heavily massaged with some pretty complex statistical math. There are a large number of factors that can influence the river's productivity and population counts. A couple of major floods had very serious consequences in the short term, but the system seems to be able to rebound over time. There have been times when there was less fish around and times when the fishes' conditions factors have been below what we normal expect. At present,  things seem to be on the poor end of the scale (especially the rainbows).  One thing about this study that I see as a blinking light.....there needs to be a standardized system established for collecting data so that we can compare numbers over years without creating fudge factors. 

No kidding. Looking at the map of where testing was performed - for the years 2003-2008 surveys were performed in the same stretch, near police, in 2011 three separate locations, including above the highwood, below police, and near Cranston, in 2012 they only sampled below the carseland weir, and in 2013 they sampled in the city, 4 separate locations from the WHD weir down to Douglasdale... I’m no biologist or statistician (and won’t try to speculate on whether the adjustment/fudge factors are sufficient to accommodate this) but those sections are not exactly the same in terms of the productivity of the fishery. Would be awesome to see them do population surveys in the same location to make year over year data more comparable... 

[fishteck]

This article has generated considerable debate on this board, our Bow River Trout Facebook page and others that have similar interests in a sustainable trout population for the Bow River. It is important to recognize that the historical Bow River fish population surveys were conducted on one of the most productive stretches of the river between Policeman's Flats and the Highwood River. And at that time were considered to be representative of the lower Bow River trout population. The 2005 and 2013 floods change that - the stretch of the Bow River below the Highwood was hit far harder than above by the two flood years and there is general belief that the fishery has never fully recovered in that area. The more recent fish surveys did include data collected from below the Highwood River and above Policeman's Flats therefore it is not surprising to see a decline in trout populations. What the data does indicate is that the trout populations across the entire "Blue Ribbon Bow River" from Calgary to Carsland dropped by as much as 50% for Rainbow Trout from 2003 to 2013.

The end result has been that AEP started a new series of fish population surveys across the entire Bow River sports fishery from Bearspaw to Carseland in 2018 to establish a baseline to develop future fishery management protocols for the Bow River. This is a significant step in the management of the Bow River sports fishery.

On the subject of variable Bow River flows - It is very easy to point your finger at TransAlta, but the Government of Alberta sets the protocol for Bow River water management. In July 2018 the daily variable flow were extreme. When we expressed our concerns for the fishery and potential impact on the fish survival itself immediate changes to the daily water management protocol were made and flows stabilized as best that TransAlta could do for the remainder of the year. The recently installed flood mitigation protocol for the Bow River may be our biggest challenge. The recommendations  presented to the GOA were flawed in so far as not addressing the impact of modified upstream dam operation on the downstream ecosystem - specifically the sports fishery and associated environment. Bow River Trout Foundation has expressed our concerns to AEP Minister Phillips - we are awaiting a response. Needless to say, it will take time to make change to water management practices to enhance the sports fishery, but we continue to be hopeful.

In closing, it may be worth following our website blog page for information on the Bow River fishery, we try to keep it up to date on current issues. http://www.bowrivertrout.org

 Bow River Trout Foundation

[fishjunkie]

I would need to see the "three different quantitative models " to decide on the seriousness of the problem. My first thought is perhaps the spawning grounds in the Highwood River might be under pressure. Have the rainbow spawning grounds been looked at in this study?  There are a lot of factors involved  and how do weight each stressors in your quantitative model?   The thing that worries me is they say don't know from their model/data what caused the population decline but are quick to suggest an easy "fix" of limiting fishing?  Perhaps there are more serious factors in decline that need addressing as well.  

[bcubed]

15 hours ago, monger said:

 One thing that is easier to measure is the number of anglers and angler effort. The angler population has really exploded over time, and the average skill level is probably increasing as well. This angler effort is one thing the government can attempt to control

The creel survey last year wasn't an accident..

[fishteck]

I believe many are looking at the Cahill's publication for more that what it is - a retrospective statistical analysis of field study data over a 10 year period. There is little accountability of the variables from year to year in any of the population studies. Statistical modelling  can account for some of the variables - but not all. Regardless, the publication does support what many have been saying for years, that the trout population is in decline and action needs to take place to stop the decline. Have a look at the following link that will take you to a summary of all the reported fish population studies prior to the 2013 flood. The trout population and proportion of rainbow and brown trout varied from survey to survey and in general the reasons for the variations were purely speculative.

Nevertheless Cahill's publication has moved focus by AEP away from exclusively endangered native species of trout to some management of the Bow River sports fishery.

I believe many of us would believe that this is a good thing. 

https://bowrivertrout.org/2018/06/13/the-state-of-the-bow-river-fishery-trout-populations-may-be-in-decline/

[trailhead]

I concur with many of the observations purported. It is a good thing to examine the management of the Bow River trout fishery. That being said how does the angler pressure compare with some of the rivers in Montana? So is the trout population really in decline, from all I have read the statistical sampling is random at best. As for the creel surveys, I was at McKinnons a few years ago and TU was doing a survey and I just could not believe how many guides told them to F+@* off and leave their clients alone it was almost every boat. Too many variables to make a judgement in my opinion. Sure the fish numbers move up and down, so does the traffic on Deerfoot on a daily basis. Go figure!

[Vitalshok]

As for the guides how many trips per season do they do on average?How Many fish do they catch a trip ?How many guides are on the bow?Take those numbers and the math is most likely outrageous  .Then you ad in regular Joes fly fishers and gear chuckers man those total fish could ad up in a real hurry that’s hard on fish.I often have 5 plus fish nights or days.Not saying any one thing is the problem but the  fish are really hit hard on the good months.Plus all the other bull crap they have to put up with.just my opinion it doesn’t matter like my wife says lol

[FishnChips]

Do fish feel pain when hooked? I feel pain when I read threads like this one.

I see a great deal of quite well informed and expressed opinion on this topic. It is commendable that our fishing community seeks to express itself. I certainly learn a lot and it does much to shape my personal opinion.

I also observe evidence of apathy, fractured consensus, ambiguous data, (our own minister Shannon Phillips declined to follow the recommendation of our own provincial biologists in Spring 2018 [WTF?]), interpretive bias and selective fact presentation which does not reveal the complete set of cascading events and distorts the complicated interactions. For example, who actually controls Bow Flow on a day to day basis? Is it in fact TransAlta or the Province? Whom can we trust to tell us the truth? This further complicates matters.

Many fine minds and intelligent people from the academy of fine ideas (Fed/ Prov government and academia) and plain old smart folks who know their rivers, their territory and can put pen to paper from Roderick Haig-Brown in BC, Tom McGuane in Montana, Andy Russell to Kevin van Tighem in AB. Just these few writers have between them more than a century’s worth of intelligent prose dedicated to educating even the most poorly educated (like me) fisherfolks on the topic of conservation. Why are we still so $£%&ed up over it? 

In the field of psychology, cognitive dissonance is the mental discomfort experienced by a person who simultaneously holds two or more contradictory beliefs, ideas, or values. This discomfort is triggered by a situation in which a person’s belief clashes with new evidence perceived by that person. When confronted with facts that contradict personal beliefs, ideals, and values, people will find a way to resolve the contradiction in order to reduce their discomfort…  (I excerpted this off the web). 

Call it, if you will, skating on thin ice. I saw this cognitive dissonance phenomenon 90 minutes ago on the Town Pond in my foothills town. The pond is not officially open as it has not met the Town’s published criteria for safety. There is a sign prominently displayed. Yet Mothers and Fathers with supposedly beloved children are lacing up to skate and ignoring the signs. You have facts opposed by a mind-set which is creating a risk and threat to their own children. 

A so-called Professional Guide behaving as quoted above to the TUC Creel Survey? Not so hard when you begin to look at the complexities of the human mind. A disgrace to civilization.

I see in this forum thread a link to the Bow River Trout something or other… (sigh). Just look at all the different organizations struggling to have their point of view heard. Federal, Provincial, Alberta Environment, Alberta Conservation, Bow River Trout Something or other, TUC – Calgary and Upper Bow Chapters… (isn’t it the same river?), the Guides, the fishing stores, the pathetic amateur drift boat owner guiding on a river (to un-informed clients) he doesn’t know because it looks good on youtube.com… (that started this past season in my area). It’s a higgledy-piggledy mess. It reminds me of the final scene in David Lean’s magnificent film Lawrence of Arabia.

Ladies and Gentlemen we have a huge problem. We need murderous, stunning truthfulness. All topics, all areas and all the time. We need a single competent authority and a unified, informed and standardized approach. The utility of the internet is at our disposal. The solution will have to be in the form of tough love. “No skating today kids, the pond is not safe” would be music to my ears.

[Sparkplug]

 

In July 2018 the daily variable flow were extreme. When we expressed our concerns for the fishery and potential impact on the fish survival itself immediate changes to the daily water management protocol were made and flows stabilized as best that TransAlta could do for the remainder of the year.

So..."Sorry for that July 2018 stuff, we couldn't help ourselves when we saw the Pool Price blow out like that...we'll try to do better from now on..."

What consequences were visited upon TransAlta from the July 2018 daily flow extreme variations?  Fines/sanctions?  Nope, nadda.

The electricity Market Surveillance Administrator hands down fines and other punishments when electricity market players misbehave...what consequences are their when a market participant misbehaves environmentally?

From TransAlta's Nov 1 2018 Investor Presentation, regarding "Upside" they see in their Alberta hydro facilities in the 2021+ time frame, when their PPA's expire (page 5):

Post PPA, TransAlta gets full revenue from energy, ancillary and renewables credits

 

Balancing Pool receives energy and a majority of ancillary revenue today

So, come (even) next year, when we've seen more coal unit retirements, more wind generation (both of which drive volatility in the Power Pool Price), and there are again those massive electricity market price spikes...what do you think is going to happen?  What about 2021+?

Frog and the scorpion fable...

 

 

[Jayhad]

Lets look at the positive, if the dirty, introduced rainbows go, perhaps the majestic browns will fill in the biomass gap..... BC guides will be gone because they are addicted to silver transplants, one can dream.

[monger]

Mr Jayhad....that is just racism against Mykiss

No guides.....now I can dream

[Dangus]

Hopefully this is When Alberta is going to start regulating guides and guide days.

My forehead vein bulges every time I have to think about the fisheries here trying to reinvent the wheel when it comes to management, when all they have to

do is look west. 

 

[danhunt]

This line in the report stuck out to me;

"The pattern of decline in adult abundance in the LBR appears similar to declines in other high-profile Rainbow Trout fisheries caused by Whirling Disease."

My understanding is that the parasite and the resulting whirling disease mostly affect young fish of a size that aren't often targeted, or even caught by most anglers.  Limiting angler effort could, in some measure, protect the adult fish and possibly allow more to spawn but would this have an appreciable impact on the number of young trout that survive the disease and live to produce the next generation?  Also, if the rainbows in the Bow aren't native (but naturalized) could introducing a strain like the Hofer rainbows that have shown a higher level of resistance to the parasite be possible, and if so would this help the population recover faster?