2018 Creel Project Results

A Note about the Minnesota Steelheader Creel Project:

Each year, Minnesota Steelheader collects and compiles voluntarily submitted creel reports of steelhead, kamloops and presumed coaster brook trout through our Creel Project page. This catch information is combined and compared against numerous data sets, the goal being to provide you with the most accurate picture of North Shore steelhead run behavior.

While the primary focus has been fish caught in the tributaries during the Spring migration and spawning run, we appreciate and accept creel reports year-round. MS analyzes reported catch dates, region caught, the numbers by species, measurements of daily flow, temperature and other open-source fisheries data, and the results are charted in Daily, Weekly and Historical formats.

This is not a scientific creel by definition. We do however incorporate, use and present as much of the available scientific literature as we can; the difference is that this is done from a fishing perspective. These tools provide an opportunity to be a more knowledgeable and most importantly, a more successful North Shore steelheader. 

Creel Project Basics and how we prepare the data

The Creel Project looks to answer questions we receive year after year from anglers:
  • When do the fish run?
  • Where do they run?
  • How long do runs last?
  • When is the "best" time to go?
  • How might I plan a trip, particularly if I have to travel long distances or only get one or two opportunities to get out and fish each year?
We use those as the basis to answer more advanced questions:
  • Are there distinct differences in run timing and duration between the various regions of the North Shore?
  • Is there a typical run timing and what does that look like for each region?
  • How do flow and temperature affect steelhead returns, fishing and presentations?
  •  What other species data can we use to corroborate "run timing"?
    These are by no means the full list, and each year we come up with more questions to explore, or some new twist that challenges us to re-think. Based on our goals, we package up all creel submissions and present the data in a variety of different ways, the basics of which are as follows:
  • Daily Reporting: Daily creel trend is plotted against both flow and temperatures to help you visualize the more granular interactions between steelhead and the primary environmental factors of flow and temperature
  • Weekly Reporting: As the run progresses, the daily creel reports are plotted in a weekly format. This removes a lot of the day-to-day noise, and helps you to visualize the overall progression of the current-year's run
  • Historical Reporting: The weekly numbers from each individual region are nested within all prior-years data to create a unified historical picture. This is done for each individual Region: Lower, Mid and Upper Shore as well as at a combined Shore-Wide level. These historical charts provide the context for looking ahead. They are not a prediction by any means, but they do provide the framework to understand the basics of any given migration: When do the steelhead and kamloops typically start, how do the runs progress along the Shore, when do they typically peak, and when do they typically end in any given year  
The following chart illustrates the data plotting and nesting concept: Mid Shore daily creel reports are used to compile the weekly data from the current year (in green). This in turn is nested within all prior year's regional data for the Mid Shore to create the Mid Shore regional historical picture (in blue). Finally, all Lower, Mid and Upper Shore regional data from 2010 to present is nested together to create a unified Shore-wide historical picture (in red). 

To be clear, the historical charts are not a prediction of what will happen in any subsequent year. They do however provide a solid framework. Knowing the time-periods in which the runs have occurred from year to year along with how they progress allows you to use current year temperature and flow data to establish some very clear benchmarks as to what is, or is about to happen on a local, regional and Shore-wide level. This information gives you a clear path to adapt to current conditions of flow and temperature, and to use the information to be a more successful steelheader during next year's run. 



2018 Creel Project Results


Lower Shore

2018 was a drag race. With the late spring and delayed start, the second the light-tree turned green we went from 0 to 200 in about 4.25 seconds. 2018 was also the year of the rapid warm-up. Over the course of just 8 days, average stream temperatures rose a staggering 11 degrees across the shore, and this had numerous impacts on fish movement and fishing. On the lower shore, we went from average stream temps of 32°F to 48°F between April 24th and May 5th.

Steelhead will migrate upstream in numbers incredibly fast under these conditions looking for suitable spawning areas. Shortly after attaining the initial major migration temperature threshold on April 30th, fish were spread throughout the various streams. Steelhead then quickly migrated as high as they could go in these systems leaving the anglers still fishing low wondering where all the fish had gone. 

We did have some very early reporting in 2018. Despite the extent of ice cover, there was just enough open water in certain areas that the air temp spikes added flow from snow-melt; this generated some exploratory fish movement around the river mouths where there was any type of open slot in the ice. These fish were primarily kamloops, but there were a couple steelhead mixed in there. It wasn't much, but a few intrepid anglers caught fish during March and late April.

The first Lower Shore reports came in on March 7th with our last submission coming on May 28th for a total of 82 days. As we saw in 2017, there were a good number of large steelhead caught in the 29"+ range. Total numbers of fish reported were as follows:
  • Steelhead: 196 for a 0.5% increase over 2017 reported totals
  • Kamloops: 126 and 72% of 2017 reported totals
  • Brook Trout: 42, for a 35% increase over 2017 reported totals
The brook trout (presumed coaster) data is discussed below, but we are seeing some interesting possible correlations between overall brook trout catch numbers, timing, location caught and rainbow trout (steelhead+kamloops) returns and timing. 

As noted in virtually all previous creel regions and years, major upstream migrations of steelhead occurred at the point average daily stream temperatures reached what Minnesota Steelheader calls the "Major Migration Threshold". This is discussed in more detail below, but it's probably the most critical benchmark you can use for planning with respect to steelhead fishing. Once MMT is reached and maintained, flow conditions become the primary influence on subsequent steelhead movement although stream temperatures still influence steelhead location within streams, particularly when temps are bouncing between the upper 30's to mid 40°F range on a daily basis.

Lower Shore Daily Data
   
The Daily chart for Lower Shore illustrates the interactions between flow, temperature and creel trend. The daily average and maximum stream temperatures depicted are actual with the dotted red line representing MMT. The stream discharge or flow is plotted at 10% of the actual figure. We do this on the daily charts simply because the flow numbers are so high in comparison to temps and creel trend, posting the flow number as actual flattens out all of the other data. This makes it difficult to see the detailed interactions between flow, temps and creel trend . The trend is a mathematical moving average trend calculated from the daily numbers of fish reported.

Reports as noted began in early March and were very sporadic. The warm days on March 27th and 28th generated increased flows from snow-melt and some fish movement, primarily kamloops. 

Ice cover on the streams was tenacious in 2018, but with rapidly warming air temps across the North Shore, the entire Lower Shore broke loose between April 17th and 20th. Despite the open water and increased flow, creel catch trend remained low. The large volume of cold runoff from snow-melt kept average stream temperatures low, as well as keeping the streams high and dirty for a couple of days. 

Snow-melt runoff and subsequent flows peaked on April 24th. This was the tipping point; snow-pack had been reduced to the point where significantly less cold runoff was dumping into the streams. This reduction in 32-34°F melt-water allowed average stream temps to rise rapidly.

Lower Shore hit the initial major migration threshold on April 30th as noted on the chart. A bump in flow on May 1st-2nd was significant enough to degrade conditions and slow creel trend. The steelhead were running, but streams dirtied up quite a bit. If you weren't fishing big, bright/dark (or smelly!) presentations and not getting it down to the fish, it was a slow couple days.

By May 3rd, flows were dropping again and with the increased clarity, we experienced our typical 10-14 day period of peak steelheading. New up-bound fish were still being caught between May 12th and May 15th, but this was all post-peak steelheading. You had to work for your fish, particularly if you remained low in the systems. 

Between May 19th and May 25th we had one last significant increase in trend. These were primarily spawned out adults dropping back out of the larger Lower Shore systems. As average stream temperatures hit the 50's and spawning has wrapped up, these drop-back fish really strap on the feedbags. Changing your approach and presentations with food in mind can yield some incredible results. The "egg bite" is largely over by this point, so thinking about all of the other food sources available to steelhead in the streams and trying some new things can really pay off.


One final note about the tail-end of the 2018 run, and this applied to the entire North Shore this year. Average stream temperatures were getting very high towards the end of May. They increased so rapidly and got so high that in-stream averages were very close to the lethal limit for steelhead on a number of successive dates. High afternoon stream temps exceeded lethal limits in a couple of cases on our index stream. Temperatures in that range cause mortality in their own right in adult fish. When close to these limits, hooking fish and fighting them, even for very short periods can kill them. Other States deal with this problem by enacting "Hoot Owl" restrictions. Hoot Owl regulations restrict angling to those early portions of the day when stream temperatures are at their lowest, and this helps reduce mortality. Minnesota hasn't had to deal with this problem in the past which is why you don't see these types of regulations. 

The choice is pretty simple, if you don't want to kill steelhead, don't fish for them when in-stream temperatures are high. For an easily digestible explanation of the problems caused by high stream temperatures, click this Temperature Link.    

Lower Shore Weekly Data
    
The weekly creel project charts better illustrate how regional runs progress over time. We present this chart because as explained above, it removes much of the noise in the daily charts. It also helps illustrate similarity or differences between annual runs from a regional perspective. It allows you to see the shifts in start, peak and end dates between one year and the next along with overall weekly reported numbers of fish, temperature and flow. 

This is the best chart to use for comparisons between one regional year's run and the next, along with comparing similarities or differences between Lower, Mid and Upper Shore run progressions in a given year. The orderliness of these weekly charts supports the hypothesis that there is in fact a very typical run progression once we have reached MMT, and that they look very similar year after year for each respective region despite differences in actual start dates. Once you know where you are at in any given run using the week of MMT as a marker, you can use the normalized regional returns by temperature illustrated a little later in this report to understand what is likely to happen over the next couple of weeks. You can plan where you are going to fish and how you are going to do it. This is all predicated on using the MMT as your starting point. We'll get into that more below.
   
The 2018 Lower Shore Weekly is a very typical picture we see year after year: Peak up-bound migration and subsequent creel catch as MMT is attained, with peak steelhead fishing lasting for roughly 10-14 days. This is followed by decreasing catch over a several week period. While the daily charts only illustrate overall catch trends, the weekly chart shows the actual creel numbers reported for both kamloops and steelhead by week, along with average weekly stream temperatures and flow. Again we post the flow at 10% of the actual figure to reduce flattening of the other data-points. To determine the actual flow average for the week of April 23rd-29th, you would multiply the flow of 27 by 10. This gives you a flow average of ~270cfs for that week. Average stream temps the same week were in fact just over 38°F, with kamloops numbers reported at 40 and steelhead reported at 65.




The granular interactions aren't as readily apparent here simply due to the weekly format, but there are a couple items of note:
  • DNR Technical literature notes slightly lower run and spawning temperatures in kamloops when compared to steelhead, and we see this reflected in the differences between peak kamloops and peak steelhead creel. Lower Shore has historically reported the highest number of kamloops to creel. This is a direct result of the efforts to limit genetic introgression of kamloops genes in steelhead through the stocking plan. As you are all probably aware of by now, cross-breeding and successful spawning of pure kamloops in Minnesota, as well as the detection of kamloop genetic influence in other State's river systems was sampled through the Steelhead Genetics Project. These findings directly lead to the cessation of the kamloops program. Click the link to learn more
  • We can't know precisely when MMT will be reached each year due to ever-changing environmental conditions on an annual basis, but there is a developing picture as to how long our typical "pre-MMT" phase lasts. We'll illustrate this in a different way below, but short of rapidly warming stream temperatures and limited or no snow-pack during this phase, our pre-MMT period seems to last anywhere from three to five weeks. Generally we see an average 10%+/- of our total creel being reported during this period, and pre-MMT returns are fairly consistent across all regions and years with the exception of the Upper Shore; more about that below
  • Post-MMT we saw our typical 10-14 day period of peak steelhead and kamloops catch
  • The week of May 14th was when we started seeing the first significant increases of catch related to drop-back fish leaving the larger Lower-Shore systems
Lower Shore Historical Data 
  
Our Lower Shore sample size is now 3221 rainbows combined reported to creel over 9 years. This allows MS to put together an overall picture of historical Lower Shore runs. The Lower Shore Creel Survey - All Time chart below illustrates the total numbers of all rainbows (kamloops + steelhead) reported by week for all years in the Creel Project: 2010-2018.

Generally speaking, the Lower Shore migration can start any time after the week of March 12th, typically having wrapped up by the week of June 4th. This is the general framework, but remember that those dates are inclusive of the very earliest migration start and latest migration end dates from a historical perspective. Much of this depends upon how early or how late the streams begin to warm and open up on an annual basis, as well as when we hit MMT.

Within that framework however, the developing picture shows a strong Lower Shore historical peak migration week of April 16th through April 22nd. These dates closely agree with and are independently supported by DNR trap numbers from the French and Knife river. As of the last Juvenile and Adult Trap Supplemental Report, the single date with the greatest numbers of rainbows sampled over time at the trap has been April 18th. The practical application from a steelhead fishing perspective is that if you are trying to plan a trip for any given year, April 16th through the 22nd is likely your best starting point. If you were a bookie, that would be your Lower Shore money-week. 

The catch with this is that we all know year to year fluctuations in weather, flow and stream temperatures are unpredictable. This makes predicting the start of major up-bound migrations more than a week or so in advance also unpredictable. 2018 peaks fell a full two weeks later than the historical peak for steelhead by way of example. 

However, understanding how MMT influences timing, and actually knowing where MMT falls in the current year helps you maximize your chances at steelheading success regardless of which region of the Shore you fish. MS tries to help you there. If you watch the blog and Facebook page, we typically post information regarding flow and more importantly stream temps right up until we hit MMT in any given region of the Shore. You can certainly catch fish during that pre-MMT time-frame. Anglers do in fact catch and report about 10% of total creel during this roughly 4-5 week pre-MMT period. Once it hits though, you typically have two weeks of peak steelheading in front of you. After that, average stream temps in the 50°F range is that dynamite drop-back phase on our larger systems across the shore.

Finally, the peaks illustrated during the weeks of April 30th and May 14th represent historical "late" and "latest" migration year peaks still apparent in the overall data. 2018 falls into the "late" run category. The very early and late peaks will likely become less apparent over time with larger sample sizes, just as shifts in the peak week may also develop in the future due to a number of environmental factors.    


The Lower Shore Creel Survey Means chart below shows you average numbers of rainbows reported by week for all years in the Creel Project: 2010-2018.

Same concepts as outlined above in the All Time chart. Strongly defined peak the week of April 16th where we are averaging 78 rainbows reported annually. Historically we are averaging 357 rainbows reported to creel annually on the Lower Shore. This number is likely to decrease over the next several years as kamloops age out of the population with the cessation of kamloops stocking. It will be very interesting to watch this over the next several years with respect to the influence of kamloops on steelhead rehabilitation.



Trap Results  


The final Lower Shore data from 2018 incorporates the DNR Combined French and Knife Trap numbers. This chart illustrates the publicly reported numbers of both steelhead and kamloops captured by trap and seine during up-bound migration in 2018.

We have included the average stream temperatures and actual average flow from our index streams by week of trap. This affords you another opportunity to see the influence of stream temperatures on initial major up-bound migrations from a different data source. MS uses this data to as a check against all of our other creel trend and the weekly regional data. 

To better illustrate temperatures and MMT threshold against the large steelhead and kamloops numbers, we multiply average temps by 10 for the purposes of charting. The index stream wasn't really 380° F at the point of MMT, it was 38° F. The weekly flow average is actual, we don't have to worry about flattening through posting the actual average flow given the larger rainbow numbers in the chart. Here the actual average flow for the week of April 30th - May 6th was in fact about 210cfs during peak rainbow trap.   

Additionally, the chart doesn't appear to illustrate the differences in steelhead and kamloops returns with regards to migration and spawning temps. With kamloops slightly lower threshold compared to steelhead, we normally see that also reflected in the trap charts. Much of the lack of difference here is simply the numbers of fish trapped by method and the timing of public reports. The French seine numbers weren't publicly reported until several days after the Knife numbers. This skewed kamloops numbers into a later week.

Given the slight differences, you can generally treat MMT temps as the same for both steelhead and kamloops for fishing purposes. We just aren't as concerned with the finer biological distinctions between the species from an angling perspective, but understanding effects of MMT on migration is still helpful. Just be aware that the differences are there because this can mean all the difference between fishing and catching, especially in cold water conditions during the pre-MMT period.  Adjust your approach and presentations to cold-water tactics and you'll be successful.

Lastly, it's important to note that that the kamloops trap depicted here come almost exclusively from French River. The French is smaller and tends to warm to MMT more quickly than other area streams. This means it will typically reach the threshold earlier than streams such as the Knife, so you tend to see more of a separation between the steelhead and kamloops return peaks. This is as a result of the combined effects of lower return/spawning thresholds in kamloops and earlier warming typical of smaller North Shore streams. Again though, the publicly reported initial French numbers came in later than the Knife numbers. We had to rely on those, and not the actual numbers captured by the actual capture date for French River. When MS can obtain those actual figures, we typically see more separation between kamloops and steelhead peaks in the trap charts.

  
All-Time Knife Trap numbers. OK, not quite... We don't have exact data points for all years of trap data; where that is the case, we have relied on the publicly reported dates and numbers from the DNR spring fishing report. We also do not have the 2018 trap numbers incorporated here for a couple of reasons not worth getting into. 

These are however historical charts showing rainbow returns to trap along the Lower North Shore. As with our other historical charts, they are not a prediction of future runs, but they do provide a framework to begin understanding the question of, "When do the fish run?" This data is very useful as a comparison point to see whether our Creel Project data has validity, and helps to substantiate other findings. There are a couple oddities here related to plotting the data which don't really warrant going into. We have plotted the long-term flow averages for Knife River for your consideration along with total numbers of fish sampled by week. Total sample size is 15,267 rainbows trapped at Knife River.

All-Time French Trap numbers, same historical charting comments as above but note the slightly earlier kamloop peak compared to the week of April 16th peak for steelhead. We plot the long-term flow averages for the old Sucker River Gage (now disabled since the 2012 flood) simply for the larger data-set for your consideration along with total numbers of fish sampled by week. Total sample size is 27,437 rainbows trapped.


Mid Shore

Our first Mid Shore reports started coming in on April 26th with our last submission on May 24th for a total of 29 days. Total numbers of fish reported were as follows:
  • Steelhead: 189 and 56% of 2017 reported totals
  • Kamloops: 22 for a 22% increase over 2017 reported totals
  • Brook Trout: 54 for a 190% increase over 2017 reported totals
Mid Shore was locked up hard through most of April, but temps rose so rapidly that it broke loose and hit MMT at virtually the same time as the Lower Shore. In fact, both the Mid and Upper Shore effectively launched at the same time as Lower Shore. While this is uncommon for Upper Shore, we do see this simultaneous major up-bound migration of steelhead in the Lower and Mid Shore regions more frequently.

One item to be aware of with respect to the Mid Shore is that our only index stream is the largest of all the Mid Shore Streams. It typically warms to MMT several days up to a week after most other Mid Shore streams. This is the only chart where MMT periodically can and does apparently lag significant increases in apparent initial up-bound migration as well as significant increases in creel. The lag time is typically small though. When all of those other smaller streams reach MMT prior to the index stream, the creel report plots typically reflect that. If we had annual access to and only used Knife River temps for Lower Shore, we would likely see the same thing in those charts given Lester, Sucker, French etc. warm to MMT more quickly drawing fish, anglers and subsequent reporting. On Mid Shore, having access to temperature data from Split Rock and others would produce more accurate results for plotting Mid Shore MMT. Minor difference but important to understand.




As with Lower Shore, MMT was attained April 30th on our Mid Shore index stream. Smaller streams hit a couple days prior and we were getting good creel reporting from them in 2018. Several flow peaks on Mid Shore limited success in the very early stages, but fishing was still very good for those willing to adapt to conditions by changing locations and presentations. There is in fact an upper flow value which will limit up-bound migration of steelhead unique to each stream. On the Knife this is well documented at around 500cfs. On the Sucker, this value is likely somewhere in the 300cfs+ range. It's difficult to say where this falls on mid-shore streams, but on the Baptism it is likely somewhere in the 900cfs ballpark. For reference, 900cfs is equal to 6732 gallons of water flowing out into the lake every second.  

Post-MMT was a crazy week on the Mid Shore with not only numbers reported but size of fish. Some VERY big fish were taken on Mid Shore in 2018. Overall numbers of steelhead reported were down from 2017 however, this was again the direct result of two very high flow spikes early in the run during peak up-bound migration which limited fishing more so than the ability of steelhead to move into and up the streams.

Average stream temperatures warmed rapidly after May 15th leading to some lights-out drop-back fishing on the Mid Shore. As with Lower Shore, average stream temps approached lethal limits after May 24th. Fortunately we got a shot of cooler weather and rain which helped mitigate these conditions. By that point, most fish had left Mid Shore systems entirely. 

In the Mid Shore Weekly chart, you can see strong early steelhead numbers just in front of MMT, again due to large index stream size compared to smaller streams which hit MMT a couple days prior and where most of the initial reporting was coming from. We didn't get quite as steep of a rise in daily average stream temperatures as Lower Shore, but it was still warm and potentially lethal on a number of days at the end of May. 

What stands out to MS in 2018 on the Mid Shore is not only the kamloops numbers, but the strongly defined peak the weeks of April 30th through May 13th. These fish all moved a significant distance up the Shore in higher numbers. Kamloops were also caught up around the island section on the Baptism which is not very common.

     
Mid shore All Time: Mid Shore has always been a bit of an enigma, but with 2177 samples a clearer picture is beginning to develop. The first peak the week of April 2nd remains from one of our earliest-recorded run years which was a very strong year on the Mid Shore. People were fishing and reporting in mid-March across the shore that year, but we anticipate this peak will become less evident with time and data. 

The April 16th - 22nd peak likely represents a true "early" run peak with respect to Mid Shore. The April 30th through May 6th peak is likely the true historical peak for Mid Shore, just as April 16th - 22nd is on the Lower Shore. The coaster data has had us thinking this for some time now, but the Mid Shore general timing has been elusive until just this year. The more defined early run peak likely comes from the fact that Mid Shore is the one region we see attaining MMT at the same time as Lower Shore on a somewhat consistent basis. The vast majority of this has to do with the number of reports coming from the Stewart. The Stewart is grouped with Mid Shore stream reports although it is more widely separated from the Split Rock, Palisade and Baptism geographically speaking. We also group the Stewart with Mid Shore since this is how the DNR creel beats are structured. This maintains continuity when comparing MS and DNR data There really isn't any way to effectively split Stewart out since we never ask for stream names in creel reports, just the region in which the fish was caught. Having 9-years worth of data reported with Stewart in the Mid Shore group would also make data separation difficult.

Total numbers of fish reported to Mid Shore creel by week for all years in the creel at left.




Mid Shore Creel Survey Means: This chart shows the average numbers of rainbows reported to creel by week for all years in the Creel Project: 2010-2018. Long term Mid Shore average rainbows reported now 242 annually. We likely won't see the reductions in average annual numbers on Mid Shore as we will on Lower Shore. There are less Kamloops on mid shore, so any overall reductions in numbers due to kamloops aging out of the population will be small. 2018 saw a 3% reduction in the Mid Shore mean numbers, primarily due to early flow conditions reducing the ability to fish effectively. It wasn't a reduction of the numbers of steelhead themselves, and the increase in Kamloops reported wasn't enough to offset.


Upper Shore

Our first Upper Shore reports started coming in on April 27th with our last submission coming in on May 23rd for a total of 27 days. Total numbers of fish reported were as follows:
  • Steelhead: 90 for an 11% increase over 2017 reported totals
  • Kamloops: 5 and 100% of 2017 reported totals
  • Brook Trout: 68 for a 109% increase over 2017's reported totals
The Upper Shore atypically launched at the same time as Lower and Mid Shore, but temperatures rose a bit more gradually overall in comparison. Fishing was quite consistent throughout and it was good fishing. If you wanted to catch steelhead in numbers with regularity on any given day after April 29th, the Upper Shore was the place to be. Stream temperatures did hit lethal limits on the Upper Shore at the end of May, but thankfully it was very short-lived in comparison to the two other regions. 
  

    Upper Shore Weekly once again shows an extended peak in creel with very good fishing considering low angler numbers. This extended roughly 14-day peak seems to be the norm for Upper Shore although we can't put our finger on why exactly that may be. More time and data is sorely needed. Note the slightly earlier peak in kamloops with respect to steelhead.





Upper Shore All Time: With only 889 fish in the sample, we're still trying to figure out what the overall upper shore picture looks like. Our biggest problem  is the lack of good data on the back-side of the Upper Shore run. The chart might lead you to believe that fishing drops off precipitously during the latter part of the run; but we simply don't have enough data from late-May into June to have any meaningful insight into just how long things last on the Upper Shore. One other possibility we are considering is that due to the prevalence of small/short run streams on the Upper Shore, warming occurs so rapidly overall during the end of May that steelhead finish spawning quickly and leave as average water temperatures reach the upper 50°F to low 60°F range. If you fish Upper Shore late, please send any reports you may have.


One other very good reason to encourage creel reports and scale sample collection is the Steelhead Genetics Project. Samples from all regions have yielded a wealth of information regarding populations of steelhead. Upper Shore steelhead also exhibit genetic introgression, so obtaining samples from a wider range of Upper Shore streams will help shape and guide steelhead management policy into the future.




Upper Shore Creel Survey Means: Lower all-time average numbers evident by week due to less people fishing and reporting on the Upper Shore. A definite lack of data from late-May into June. The chart probably shouldn't drop off like that, but again we don't quite know; perhaps that is really it. Long term Upper Shore average rainbows reported now 99 annually.



Shore-wide Historical Creel Survey

The Shore-Wide Creel Survey - All Time represents the unified picture for all regions of the shore: Historically earliest start, peaks, end and total numbers of fish reported by week. It's the "big picture" with each Region's annual numbers nested within the chart. This provides you with an "At a glance" reference for historical North Shore steelhead returns. Each peak from left to right beginning with the large April 16th - April 22nd peak roughly represent historical creel peak for Lower, Mid and Upper Shore. The peak the week of April 2nd through April 8th was a strong and early run year that is still evident in the chart. The Upper Shore peak is not quite as defined due to low late-season reporting from that region.


Coasters and Steelhead
   
The brook trout charts are an interesting by-product of the creel project. In the early days of the project we were simply curious about brook trout (presumed to be coasters) reported during the spring creel, but didn't really know if or how the data was usable other than to satisfy general curiosity. We know that coho are frequently taken close to shore in the spring, likely foraging on concentrations of smelt which are staging for their own spawning runs. We also observe the same apparent type of behavior in the brook trout themselves during fall. Historical accounts of "Rock Trout" occurring near-shore being caught by anglers as early as July are well known during the pre-pink salmon era. Contemporary reports frequently associate presumed coasters with fall pink runs. We think although we don't know for sure, that the coasters are entering the streams in August and September to take advantage of an abundance of free-drifting eggs from spawning pinks as a high-energy food source. This is probably a good strategy given the rigors of spawning taking place later in the fall among coasters.
   
Since these fish are making their living in and around near-shore habitat, it would make sense for them to also take advantage of other species in a similar fashion. We are beginning to think spring steelhead and kamloops offer them just such an opportunity.
   
When we looked at our coaster data, we saw a signature in that creel data which looked awfully familiar. These fish are more than five months out from spawning and we began to wonder what they were doing in the streams in seemingly higher numbers.




We next plotted the regional and shore-wide coaster data, then plugged in the regional peaks from the historical rainbow data. While we don't get exact correlations, it does get more interesting when you compare the two:



Lastly we plotted the Shore-wide historical charts for brook trout and rainbows together. It is difficult to ignore the correlations in the overall return period as well as the strong correlations to Mid and Upper Shore peak rainbow return to creel. There are also some subtleties here to consider. While it is not as apparent in the chart below, if you compare both Lower and Upper Shore regional brook trout peaks to their respective regional rainbow peaks independantly, you see apparent correlations. The Mid Shore peak correlation as shown is very strong. Part of the thought here is that with the lower prevalence of coasters in the creel on the Lower Shore, but much higher in the Mid and Upper Shore, it may or may not lend some insight into presumed coaster populations and densities. Are they utilizing other species spawning runs as a food source, and how might they be eking out a living in Superior's oligotrophic environment?
 

The last item to note is that we are not using this spring brook trout data for fishing purposes. It has however become a way to use a seemingly unrelated type of data to potentially understand more about the steelhead. If the premise holds true and coasters are taking advantage of free-drifting steelhead eggs as an alternative high-value food source, it would make sense that increased coaster presence and catch might correlate with peaks in steelhead returns. Or maybe it's just a fluke, only time and an exciting new project will tell. More to come on that initiative very soon.





Information Regarding Stream Temperatures and the "Major Migration Threshold"

When you read fishing articles related to steelheading, one of the primary influences on steelhead movement mentioned is flow. From a biological perspective, migratory fish such as steelhead and salmon are programmed so to speak to run on high flows when available. High flows offer these fish the best chance at bypassing obstacles and barriers. It also provides the best chance to reach the upper regions of any given watershed. These uppermost areas offer the best habitat, not only for spawning, but the habitat necessary for young fish to survive: Clean gravel, oxygenated water, proper temperature ranges, woody debris, abundant food, critically-sized substrate and protection from predators.

The prevailing explanation is that essentially, flow is the be-all end-all in steelhead fishing and steelhead movement. This held true on the North Shore except for when it didn't. This happened quite often and was an observation that really drove us nuts. More specifically, the flow adage did not hold true at all during the early portions of the season when the water was cold. Something was going on in the North Shore environment which appeared to be different with respect to the question of flow and "When do they run?" Anecdotally we were also interested in getting at the science behind what MS calls "Magic 40". Magic 40 is a rule of thumb term MS uses to describe a number of things but from a steelheading perspective, it relates specifically to the effectiveness of bait vs. fly vs. hardware presentations along with overall fish activity in a given stream at given temperature ranges.

After re-combing through the DNR technical literature, we found references to the temperature ranges at which steelhead typically begin up-bound migrations in very high numbers. This seemed to explain why you can have ideal flows at low water temperatures, but not be catching let alone finding fish early in the run. What we did at that point was to use all of the available Minnesota DNR trap data to create charts showing both the total returns by temperature, and those which fell specifically within the early cold-water temperature range. That range corresponds to early-season conditions; or what we now call, "Pre-Major Migration Threshold".

DNR fisheries literature for the North Shore discusses this although they don't use the term MS has adopted to illustrate the concept. And while it is more complicated than what we typically present, the basic threshold for initial major migration (MMT) of up-bound adult steelhead occurs when average daily stream temperatures reach and maintain approximately 38°F. We're not talking about a single starting point here where all steelhead suddenly take off, we're really talking about numbers and movement of steelhead that are significant

Up-bound migration does in fact begin prior to the threshold. We know from both the Creel Project as well as DNR Fisheries Trap data that approximately 10% of steelhead and kamloops return to creel and trap prior to MMT. Once MMT is attained however, all of our annual data for each region demonstrates that high numbers of adult steelhead, 85-90%+/- return over the next 3-5 weeks. The majority of those in the 7-14 days immediately following MMT.     

From a fishing perspective, there is variability in MMT between each stream. Smaller streams reach this threshold sooner as they to warm to MMT more quickly than larger streams. Our Lower Shore index streams (streams that have temperature data packages on them) are all smaller and tend to hit the threshold several days to up to a week prior to larger streams such as the Knife.

High flows also have an affect on fish movement related to MMT. Streams with flows above known up-bound limiting rates at the time MMT is reached will show delays in up-bound migration as reflected in the trap and creel numbers. A good example of this is the Knife. The known discharge limiting threshold is right around 500cfs. Above this value, up-bound migrations of steelhead and kamloops effectively ceases. The point being that fish already in the system tend to ride it out by holding tight in areas where they can avoid high current speeds. New fish move into the system in low numbers if at all despite having reached MMT. When flows drop below 500cfs, fish movement resumes. Depending on how long it takes for flows to drop below limiting discharge/flow rates, there may be a fairly significant delay between MMT and up-bound movement when flows are high. We saw this illustrated very well on Mid and Upper Shore streams in 2016. 

This is something to keep in mind. You need to adapt presentations and tactics in those raging, chocolate yeti conditions. Using more weight, much bigger baits/flies, much brighter or very dark colors, potentially using scent, and fishing in out of the way quieter water such as inside bends and below points during high flows are a few examples.

There are a total 21,578 rainbows in the DNR Trap samples below. The pre-MMT returns are a pretty consistent 10-11%, and these numbers all predate MS Creel Data. The subsequent MS Creel numbers have been nearly identical on an annual basis except for Upper Shore. Peak returns occur in the magic 40 range, and 89-90% of adult fish are trapped after MMT is met. Note the slightly lower return temperature threshold with respect to the peak exhibited in the kamloops data.





Relying solely on the above trap data, it appeared to answer the question as to why early season (read cold water/pre-MMT) numbers anecdotally appeared low regardless of flow conditions. It also appeared to explain why in warmer/post-MMT conditions, steelhead seemed to behave and follow the accepted rules of flow with respect to the North Shore.

Once we had that information, we designed a way to analyze the regional creel data in the context of the temperature numbers. Despite a much smaller sample size of 6,287 rainbows, the results are nearly identical to the DNR Trap data.

What you see depicted below are each region's total creel returns plotted by week and normalized for what we call here "Zero Week". The zero week represents the point at which each region reached and maintained the major migration threshold temperature for each year in the creel. All returns falling in the pre-MMT temperature range are depicted as a separate curve, as well as a rough depiction of when the streams hit magic 40. Note that the pre-MMT and post-MMT percentages largely correlate with the independent DNR Trap Data. Mid-Shore reported a far higher number of Kamloops in 2018. Up until this year, Mid Shore pre-MMT percentages had consistently been ~11% annually. With kamloops slightly lower return thresholds, it drove the pre-MMT percentage up.



As you can see, the one annually consistent exception is the Upper Shore at ~3% pre-MMT returns. We'll need more data to understand this, but we have a hypothesis as to why pre-MMT creel returns are relatively low for the Upper Shore in comparison to all other regions.

What we think is going on here is that kamloops are driving the higher pre-MMT percentages on the Lower and Mid Shore simply because there are far more of them present in those regions, and they tend to begin returning to the streams at lower temperatures compared to steelhead. The low Upper Shore Kamloops numbers are a direct result of the prior kamloops stocking protocols designed to limit genetic introgression in steelhead. Since there are far fewer kamloops present in the Upper Shore region from year to year, the pre-MMT or early return numbers and percentages should in theory be lower based upon known migration and spawning differences related to temperature in kamloops.

The by-product of these charts is that if you wanted to know what a typical run looks like on a year to year basis, these charts are very probably it for each region: Up to four weeks of pre-MMT run activity with 10-11% of adult rainbows returning to the streams and available to steelhead anglers. Once MMT is met, there is a 10-14 day period of high rainbow presence and activity in the streams; your best chance at steelheading success. Overall, runs can last up to 5 additional weeks from MMT, with subsequent pushes of fish largely driven by increases in flow. The highest availability of rainbows in any given region then would be in the neighborhood of 28 days of peak fishing activity on a year to year basis with some overlap Shore-wide. The actual period of rainbow availability is much longer although in-stream population numbers are much lower on both the front and back-end of the run in any given stream.

If this is in fact valid, the proof will be in the pre-MMT percentages. Decreasing kamloop numbers as they age out of the return population should theoretically be reflected as corresponding decreases in pre-MMT percentages, particularly on the Lower Shore. Pre-MMT steelhead-only numbers have yet to be fully analyzed, but we think those are on the order of 3-5% of total creel as we see in Upper Shore data. We are in fact tracking the steelhead-only MMT progressions, but we want larger data-sets before posting.  

Given the picture being developing using your data in the Creel Project, the steelhead season in Minnesota is something like 60+ days on average with about 20-25 days of peak fishing. If you're willing to follow the migration as it develops from Lower Shore through the Mid and Upper Shore, it's a pretty sweet deal for a steelheader.

MS Creel Project Raw Numbers by Year

    Quick chart on the raw reported creel numbers for each species by year:




Last but certainly not least, our sincere thanks and gratitude to all of the hardworking folks at Minnesota DNR Fisheries. Your dedication and commitment to the management and preservation of natural resources in the State of Minnesota does not go unnoticed and is greatly appreciated, Cheers!
All of us at Minnesota Steelheader hope you find this information interesting, informative and useful. From all of us at MS a BIG thank you! Without your participation in the MS Creel Project none of this is possible.



 
Best of luck, good fishing and we'll see you on the water-
Minnesota Steelheader

Comments

darklake said…
Great stuff you folks put out there. Thank you so much for all your time and talent. One comment: I've been told that the coasters are following the suckers in and eating sucker eggs. The correlation with the steelhead migration is largely coincidental, as the suckers would provide a vastly larger source of food.

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