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30-12-2015, 12:23 PM #1
Findhorn - Historic Catch Data
Happy New Year everyone. Following my work on the Deveron, I have now turned my attention to another favourite river, the Findhorn. I hope that you will find the following graphs interesting and feel moved to offer some comments that may assist further research. All of the data displayed is courtesy of Marine Science Scotland: any interpretation is my own.
The first stacked graph shows how historically the Findhorn had a small grilse catch that broadly marched in step with the MSW catch. Then in the early 1980s, something changed: the grilse catch shot up and remained high until the last 2 years. Are there any theories to explain this extraordinary shift?
Findhorn MSW & Grilse.jpg
The second plain-line shows the MSW catch and the 20 Year Average. You will note that the 20 YA has trebled over the past 60 years. However, it appears to hit a plateau around 2000. You will also note that the Findhorn MSW catch, whilst highly variable, does not display the extremes of the Deveron. Despite a run of poor years 1996-2003, the period 2004-2011 includes 5 years that rate amongst the river's best ever. Does anyone have an explanation for the plateau?
The third graph shows the combined total rod catch and the 20 YA. It underlines the extraordinary effect of the "grilse surge" on the overall rod catch - the 20 YA has grown 5-fold over the 60 years. Once you add in the grilse, then you are looking at some huge year to year variations - up to +/- 2250 fish between years.
Unlike the Deveron which has shown a complete shift from spring to autumn, the Findhorn remains weighted towards the summer, principally June and July. However, direct comparison is difficult because the Findhorn's season ends in September, whereas the Deveron's close is at the end of October.
The Findhorn's correlation between water levels and catches is not as high as the Deveron's, and is further complicated by the effects of the various obstacles along its course. As a result what may be good for the lower river is not necessarily so for the middle and upper, and vice versa. I shall do some further work and post it on this thread in due course.
All feedback and comments gratefully received.
Last edited by MCXFisher; 31-12-2015 at 03:08 PM.
30-12-2015, 02:35 PM #2
- Join Date
- Sep 2009
I'm wondering why did you use a 20-year average instead of a 10-year average.
30-12-2015, 03:52 PM #3
01-01-2016, 12:21 PM #4
- Join Date
- Jan 2009
Very interesting to see the growth of the average catch in a catchment I hold up as the least damaged in the UK (of the major salmon rivers). Was there a history of estuary/inshore netting that suppressed catches?
The fecundity of salmon is changing (less years per life cycle = more adult fish), but this surely can't have offset the declining marine...I have discounted the argument there more rods fishing harder and better with improved methods as speaking to historic Findhorn rods the worm and upstream mepp did great damage in the past and are no longer used/permitted.
Also very pleased that after an incredible week in 2011 when my party bust the long standing beat record, I sat out the poor years of 2012 and 2013! Went back this year in early August to Lethen and had a red letter week as the grilse piled through the beat.
Last edited by Bann Special; 01-01-2016 at 01:08 PM.
01-01-2016, 01:09 PM #5
Findhorn - Catch and Flow Data
Following my last post on the Findhorn's catch trends over time (sadly there has been no feed back to date), I have now looked at the relationship between water flow and catches.
The summary of the 50 year period is shown here: owing to the extreme variability of the grilse catch I have excluded this in the interests of clarity.
Findhorn MSW Catch vs Flow.jpg
The graph doesn't tell you much, other than perhaps highlighting the effects of a few especially dry years. However, because the Findhorn's catch is relatively evenly spread through the season, there is a much lower correlation between catch and whole-season average water levels than on the Deveron.
This is evident in the 20 year series 1987-2007 (chosen for consistency with my Deveron work).
Findhorn Water Level and MSW Catch.jpg
There is also the question of changing methods and the shift towards fly-only. This is potentially significant on the Findhorn, because there are several stretches that used to offer highly productive prawn and worm fishing in low water conditions; and others, spinning in high water. As an example, on the Upper Findhorn, the Tomatin House annual catch figures reduced dramatically with the end of spinning and bait fishing.
Some of my earlier work on Just One Week examined the relationship between water levels and catches at Tomatin and demonstrated a strong correlation over a 10 year period. It also looked at the combination of levels and variability (i.e. the effect of spates) on catches, where the combined correlation was very strong. Accordingly, I looked at the whole river data sets to see whether a similar correlation existed.
The first graph covers the 20 year series:
Findhorn Spate Variance and MSW Catch.jpg
in which the correlation is low.
In an attempt to take out the changed methods issue I also looked at a shorter sequence of just 10 years.
Findhorn Spate and MSW Short.jpg
Again, you can't identify a clear cut linear relationship. However, there is one factor that does stand out in the previous graph, which you might regard as common sense, under the Epicurean* theory of "not to much, nor to little, but just right". You will note that there is a cluster of good catches with the flow variability in the range 15-20 on the horizontal axis. In that range most of the catch data points are above the trend line; whereas beyond 23-25, the majority are below it. The freak catch of 1995 has to be disregarded as just that. So it is no surprise therefore to conclude that the Findhorn fishes best with a decent water level interspersed with a regular succession of significant spates. Indeed it's a blinding glimpse of the obvious, but at least there's some data to support it.
Happy New Year
* Epicurius was an early Greek philosopher who always sought the middle way. Unfortunately this led to his demise, as according to popular legend he was run down and killed by a bullock cart when walking in the middle of the road on his way home in the darkness whilst drunk.
Last edited by MCXFisher; 01-01-2016 at 04:43 PM.
01-01-2016, 04:54 PM #6
01-01-2016, 05:09 PM #7
- Join Date
- Mar 2013
- Derbyshire Hills
I know that this is difficult to quantify but I assume the catch records can only reflect actual fish and cannot also reflect rod effort.
It may be my selective memory but the current salmon fisher appears to be more passionate better equipped and willing to fish in less conducive water/weather conditions than the majority of salmon fishers when I started . With the advent of Fishpal etc and the internet do you feel also that there has been extra fishing effort as previously estates were letting on a weekly basis whereas now there is more availability on a daily basis where the weekly lets have not been achieved and this could lead to increased catches at times.
When I started ( a long time ago ) as I young man I was much keener that the majority of "older" guests on the beats I fished. The fishing was very much 9.00 to 5.00 with a decent lunch etc etc. If fish were plentiful they fished but if the conditions were not great they talked and drank and relaxed.
01-01-2016, 06:22 PM #8
01-01-2016, 09:01 PM #9
I think pre 1950's effort was probably sporadic at best. By the 1990's effective effort was very high. A boom in capital values fuelled by timeshare encouraged serious angling effort with all methods and very effective tackle. I think effort and effectiveness has slowly declined ever since, with fly becoming dominant and anglers with less time, less detailed knowledge of water.
01-01-2016, 09:28 PM #10
Last edited by MCXFisher; 01-01-2016 at 09:28 PM.