2017 electrofishing report

A bit later than normal but the Spey Fishery Board Electrofishing report for 2017 has now been published. The report can be accessed from the following link

Spey 2017 Electrofishing report

If you have any questions please get in touch via the comments or directly to research@speyfisheryboard.com

The report summary is provided below:

Summary
• The 2017 cohort of salmon fry was strong with high fry counts/densities across most of the catchment.
• The salmon fry index results from the Spey mainstem were the highest in the series which runs from 2012 to 2017.
• Downstream of Spey Dam all but two of the salmon fry index site results were in the moderate to very good categories.
• Upstream of Spey Dam salmon fry were widely distributed and the fry counts were the second highest since 2012. A very strong correlation between salmon fry in one year and parr in the next was demonstrated.
• In contrast to the fry the 2017 1+ salmon parr cohort is weak with low counts in the Spey mainstem and in many of the larger tributaries.
• Salmon fry counts in the Avon catchment were found to have recovered well after the very low counts recorded in 2016, although parr counts remain low. This was a consistent finding across most parts of the catchment and is considered to be a consequence of redd washout during Storm Frank.
• Salmon fry index surveys were completed in the River Calder for the first time.
• In the Fiddich salmon fry densities were similar to 2014 but the parr densities were lower. A recovery in parr densities is expected in 2018 due to the strong 2017 fry year class.
• In the upper reaches of the Fiddich salmon fry abundance, and range, recovered fully after the very low 2016 figures.
• In the Feshie some sites were not surveyed due to high water levels. Where surveyed the overall pattern was similar to elsewhere with fry densities up but parr down.
• In the Tromie catchment several the sites demonstrated improving juvenile salmon densities, and in the most peripheral site, salmon were present again after being absent in 2014.
• In the Calder the juvenile densities were low, despite what was considered to be benign overwinter conditions. Low abundance of spawning adults is considered to be a factor. Carrying capacity may also be reduced due to the increasing incidence of extreme flows.
• Salmon and trout parr densities in the burns were found to be very stable in comparison to 2014 with virtually identical average densities.
• The average salmon parr density in the stocking monitoring sites was the highest recorded, primarily due to good results in the Tommore and Knockando burns. Increased smolt production is anticipated from the Tommore Burn in 2018.

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Spey Fishery Board

Spey electrofishing update

The water butts on my greenhouse have been virtually full for the last month, due to frequent top-ups from heavy showers.  Despite this the Spey, and tributaries, remain relatively low? Taking advantage of these good conditions for surveying we have cracked on with the electrofishing, mainly the timed salmon fry index surveys but also some quantitative surveys.

We have completed the repeat timed surveys of  the Avon, and Livet, to assess the population after the very low counts last year in the Storm Frank aftermath. Today we also completed the salmon fry index surveys in the Fiddich and last night we hosted the annual ghillies outing to the two middle monitoring sites in the Burn of Tommore to assess the population of stocked salmon parr in that burn.

It has been a week of contrasts so far; on Tuesday we completed the upper Avon salmon fry index surveys where we usually find the sparsest salmon fry population and the smallest fry, and today we did the Fiddich where in 2014 we achieved out highest salmon fry counts.

The salmon fry index survey results for the Avon catchment are shown in the table below.

It was good to see that the salmon fry counts had recovered to a similar magnitude to those recorded in 2013. The overall pattern is the same with the highest counts in the lower reaches, declining with altitude. The contrast with the very low counts from last year are stark. Take the results from site TA15L1 for example, (this site is just above Greys Run towards the upper end of the Ballindalloch beats). Last year we could only catch 4.3 salmon fry per minute, or 13 during the three minute survey. This year, and in 2013, we managed to catch over 240 in three minutes.

The upper Avon counts are generally low, primarily in our view to low productivity. One interesting site, which was an anomaly in 2013 and in 2017 is site TA84L1, which is downstream of the Allt Loin Bheag. This tributary is only accessible to fish for a short distance and is therefore insignificant as a fish producer itself but it, along with other tributaries in the area,  create a little pocket of productivity in an otherwise very low nutrient environment. In 2013 and 2017 the fry counts at this site were higher than those recorded in sites upstream and downstream. I also had a quick look at the mean size of fry from that site and found that they were 42mm compared to the low to mid 30mm for neighbouring sites.

A little green oasis. This tributary, which joins at the Avon at virtually 2000ft altitude is clearly more chemically rich than the Avon mainstem. In the vicinity of the confluence and for a short distance downstream the river bed supports mosses and, at this time of year, algae. This type of primary production must elevate the invertebrate population a little resulting in larger, and slightly more abundant fry.

The results from the Livet, one of the most productive of the Avon tributaries, were good with the fry counts four times higher than last year (Storm Frank affected).

Salmon fry index results from the Livet. 2016 was the first year that we did this type of survey in the Livet (except for a single survey in 2013) so there is not much of a baseline but the fry counts in 2017 were all in the good to excellent categories with one site in the super abundant category! The mean fry count in 2017 was more than four times higher than in last year.

Today we intended to have a relaxed day and I would have been happy to have made a good start on the Fiddich salmon fry index surveys. However, we were on a roll and in the end we completed all the monitoring sites in the Fiddich, with some pretty impressive results.

The mean fry count in 2017 was lower than in 2014 but the size and biomass of fry present in the sites downstream of Dufftown was incredible. As with the Livet all the Fiddich fry counts were in the good or excellent category with one coloured blue (reserved for counts greater than 100 per minute).

The record sheet for the site below the Balvenie warehouses is shown below (with one of the upper Avon sites for comparison).

Salmon fry index survey record sheet for the Fiddich at Balvenie and the Avon at Faindouran. Hopefully readers will be able to make out the figures. In the Fiddich site we caught 316 salmon fry  (in three minutes), excellent but the most remarkable feature was the size of the fry. The largest was over 100mm (to be confirmed by scale  reading) with all sizes from 50mm to over 95mm represented. A few large parr were also captured. The growth exhibited by the salmon fry in this Fiddich site means that many will potentially be large enough to smolt as one year olds; if they survive the winter. There were about 5 large fry per square metre of the river bed and with such a huge concentration of prey it was a wonder the place wasn’t infested with predators. Note the small size of the upper Avon fry in comparison, in fact all the Avon site parr, some of which could be three year old, were smaller than the largest of the Fiddich fry, which were only months old. Jim and I have a few years electrofishing experience between us and we agreed that what we witnessed today was unparalleled. There are reasons for this exceptional productivity of course: the temperature of the Fiddich is elevated by all the distillery discharges upstream and there may also be organic enrichment. Whether this is a good thing or not remains to be seen.

 

A jumbo salmon parr of 147mm from the Fiddich today.

Yesterday evening we completed the remaining two monitoring sites in the stocked Burn of Tommore. Readers will no doubt be aware of the Tommore project. The Tommore is inaccessible to migratory salmonids due to an impassable road culvert and has been stocked since 2012, From 2013 it has been stocked with fin-clipped 0+ salmon parr from the Sandbank Hatchery. The monitoring results from the remaining two sites last night were the best recorded there over the last four years with the salmon parr density at one of the sites reaching 34.5/100m2; high enough to make it into the excellent category in the SFCC Moray Firth Classification scheme.

The mean salmon parr density in the Tommore Burn was almost twice as high a recorded in previous years, with improved densities at all four sites. Explanations for this good result from the Tommore stocking were discussed last night. The trout parr density has remained relativity stable since 2013 but the number stocked in the burn in the autumn of 2016 had been reduced. Perhaps this is a case of less means more? Another factor could be that the number of smolts trapped in 2017, as they emigrated from the burn, was the lowest over the three years of trap operation so it is possible that a higher proportion had remained in the burn for an additional year . although the size distribution didn’t suggest that was the case.

 

Electrofishing survey sheet from site SA1b in the Burn of Tommore. 29 salmon parr were caught at this site. Note the absence of salmon fry due to the impassable culvert downstream.

The Burn of Tommore appears to be supporting a good population of stocked salmon parr this summer; based on that we would expect the number of smolts to higher next year, potentially significantly higher.

 

 

 

 

 

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Spey Fishery Board

Spey 2016 electrofishing report

The Spey expends considerable resource on monitoring each year, mainly by juvenile surveys (electrofishing) and smolt trapping. This is an important activity for a river of the Spey’s stature; it is essential that management decisions are based on an informed understanding of the status of juvenile stocks in the river.

In 2016 we completed the Spey mainstem annual salmon fry index surveys as well as year 2 rota tributaries, primarily the Avon and Truim. The major event affecting juvenile stocks in 2016 was the extreme high flows that hit the east of the catchment during Storm Frank but also in early January when even higher flows occurred in the Livet. The 2016 electrofishing report can be found here.

In the mainstem the salmon fry counts downstream of the Avon were about half of the previous year but upstream they were close to average upstream of the Avon confluence, with particularly good results from the upper river in the area from Spey Dam to Kingussie. Upstream of Spey Dam salmon fry were limited in distribution and for the first timed more prevelent in the very upper reaches and almost absent in the usual area upstream of the dam. The salmon parr counts in the mainstem were good, the highest on average if the impacted and volatile results from above Spey Dam are excluded. A high proportion of these parr were large enough to smolt in 2017.

The area of most concern was in the Avon where the mainstem salmon fry index surveys revealed a dramatic decline in the fry counts with lesser. although still concerning, declines in the parr. In the Avon tributaries the situation was better with good salmon parr densities. The status of the juvenile trout population in the Avon continues to be good. Given the significance of the Avon the intention is to repeat the Avon mainstem salmon fry index surveys in 2017, along with some of the tributary sites to establish if the juvenile stocks have recovered naturally.

The results from the Truim also exhibited a reduction compared to 2013 but it is important to distinguish between fluctuations in juvenile densities and long term trends. 2013, the last year when the Avon and Truim were surveyed in detail were years with high juvenile stock status. The declines noted in 2016 are explainable; the extreme high flows being the most likely cause resulting in redd washout. In 2015 the comparison with the results from the 2012 monitoring cycle were good with fry and parr densities up in almost all of the tributaries monitored.

In the 2016 burns monitored (those flowing directly into the Spey) the situation was one of stability with little change compared to the same sites when surveyed in 2013. This suggests that the impact of the high flows was higher in the larger watercourses, where stream power is so much greater.

Overall, whilst the winter spates had an impact the situation is relatively good, especially in comparision to other rivers. It is worth recording that declines in salmon fry densities/counts in 2016 were not restricted to the Spey, news regarding declines in Welsh rivers even made the BBC website. The reasons for the widespread nature of these low fry counts are likely to be varied (high temperatures were suggested as a potential cause in Wales).

Our understanding of the status of juvenile stocks in the Spey remains at a high level. In 2017 the major tributaries surveyed will be the Fiddich, Feshie, Tromie and Calder, as well as the annual salmon fry index surveys in the Spey mainstem.

 

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Mainstem electrofishing survey results 2016

I should begin this blog with an apology for the lack of news from the research team recently; a combination of solid fieldwork during the summer weeks and house renovations at home has left little time for updates. Hopefully normal service will be resumed from now on – there is a bit of a backlog to publish!

This blog will focus on the mainstem juvenile monitoring which is such a prominent and important part of our work. It’s importance is a reflection of the quantity, and quality,  of available habitat in the Spey mainstem. Our primary monitoring technique for assessing the mainstem are a series of replicate salmon fry index surveys conducted mainly in shallow riffle or run habitat i.e. salmon fry habitat. These sites are surveyed annually for three minutes (actual electrofishing time counted down by the Efishing kit). The main target species and life stage is salmon fry but we also catch parr plus other species such as trout, eels etc.

The Efishing backpack was purchased in 2012 and the sites have been surveyed in a consistent manner since.  The salmon fry index results from these surveys over the last five years are shown below.

ms-fry-2016a

Spey mainstem salmon fry index results 2012 to 2016 (number of salmon fry per minute). Results are ordered from the lower river (top of table) to the upper limit of salmon distribution above Spey Dam (bottom of table).

Looking at the results as a whole the mean salmon fry counts in 2016 were the lowest in the sequence, although the pattern was not consistent across the river. We normally begin these surveys in the lower river and it was obvious from the first day of surveying this summer that the fry counts in the lower reaches not as high as recorded in recent years. This remained the case until we reached the sites upstream of the Avon confluence. The Avon joins the Spey between sites S096R1 and S104L2. Upstream of the Avon the results were better, more akin to those recorded in previous years. The change in the colour coding in this area of the river should be apparent from the table above. Note that the colour coding ranges from red (lowest 20% of results) to dark green (highest 20% of results) with amber, yellow and light green between.

Looking in more detail the average fry count in sites downstream of the Avon confluence was 10.8/min in 2016 compared to over 20/min in each of the preceding three years. Upstream of the Avon confluence, to Spey Dam, the mean count in 2016 was 21.7/min, just below average for the last five years and the third best mean count for this part of the river. There were some good results in this part of the river with much more green in the colour coding.

Upstream of Spey Dam should really be treated separately as the fish passage problems known to exist at Spey Dam have their own impact on fish numbers in what should be extremely valuable spawning grounds for early running grilse and salmon. In 2016 we found that salmon fry were limited in distribution upstream of the dam, the greater prevelence being in the upper reaches; the opposite of the more normal situation when counts are usually higher in the lower reaches, closer to the dam.

below-allt-yairack

An example of the typical good spawning habitat available in the very upper reaches of the Spey mainstem, in this case, a short distance downstream of the Allt Yairack confluence.

The picture therefore is one of lower fry counts, better in the upper mainstem; although it is worth noting that overall the counts were only a little lower than recorded in 2012.

Salmon parr are also captured during these surveys. The salmon parr counts are shown in the table below. The survey sites are a combination of historic sites (some of which had been surveyed for a number of years prior to 2012, although with different electrofishing equipment, which cruically lacked the in-built timer) to more recentlt selected sites. Habitat quality varies across the sites with some more suited to fry than parr and vica versa. A good example of this habitat variation can be seen in the part of the river from the lower Abernethy site (S163L1) to the Kingussie area (S254R1). Here substrate sizes are dominated by pebble rather that cobble and boulder. The larger substrates normally provides more cover (hidey holes) for parr whereas the smaller fry can find shelter within, or alongside, smaller material. Whilst parr counts are generally low in this part of the river the fry counts are generally good – reflecting habitat suitability at our survey sites.

ms-parr-2016

In contrast to the lower mean fry counts the parr counts in 2016 were almost the best in the sequence, beaten only by 2013. If the results from the river upstream of Spey Dam are excluded the parr counts downstream of Spey Dam were 4.9/minute compared to 4.6/min in 2013. That year was one of the few when good parr counts were recorded above the dam. Interestingly these findings chime with comments made by anglers and many ghillies this year who have remarked on the greater numbers of parr seen rising and latching on to small flies.

In addition to the network of timed sites on the mainstem we have also, since 2014 at least, completed semi-quantitiative surveys at three sites in the mainstem; at Aberlour, Blacksboat and Advie. These sites are quadrat sites, in relatively stable habitat with the site boundaries defined by boulders. These sites are completed at the end of the summer survey season and provide an opportunity for cross referencing with the timed surveys. I have commented before on the need to understand the size distribution of the salmon parr and consequently the proportion of the parr stock that is likely to smolt the following year. These end of summer surveys in the mainstem provide the sort of data we need to investigate this issue. Incidentally semi-quantitative surveys means those involving a single run through the site and in this case without stop nets (it would be virtually impossible to set up stop nets in a quadrat site in the mainstem anyway).

Results from the semi-quantitative surveys in the mainstem 2014-2016

Results from the semi-quantitative surveys in the mainstem 2014-2016 (density per 100m2). In two out of the three sites the salmon fry densities were the lowest in the sequence in 2016, matching the general findings from the salmon fry index surveys. And, similarly, the salmon parr densities were the highest in the sequence at all three sites.

Site S7 in Aberlour

Site S7 in Aberlour. This site has been surveyed in exactly the same way for the last three years at the end of the summer. 100 salmon parr were captured within the marked area, with many more evading capture within the luxuriant fronds of ranunculus which grows so well in this area.

 

spey-mainstem-sizes

This table provides data on the mean length of each size class along with the proportion of salmon parr likely to smolt the following spring. For example in site S7 (Aberlour) 85% of the parr were larger than 90mm (the end of summer size threshold likely to result in smolting). Within that site the actual number of pre-smolt parr was also 85; twice the number recorded in the 2014, the year with the second highest count. In each of the three sites, even though the mean parr length were smaller than recorded in 2015, the actual number of pre-smolt parr was the highest in the sequence, although with only three years data it is not really a long term series – yet.

The results presented here today are therefore mixed. Salmon fry counts in the lower mainstem are lower than recorded in recent years but the parr counts, and densities, in the mainstem appear to be good, indicating thaat the mainstem should produce a healthy smolt run in 2017. The parr  of course need to survive the winter; some level of mortality is inevitable with the main risks being extreme flows (although maybe less of an issue during the winter), predation and the avaibility of overwinter habitat.

Potential reasons for the reduced salmon fry counts in the lower mainstem this year will be the subject of the next blog; but from discussions with other biologists it is clear that this is not a phenonema unique to the Spey.

 

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Spey 2015 electrofishing report

The report of the electrofishing surveys carried out by the Spey Foundation in 2015 is available to download by clicking here. This is a comprehensive report covering the results of the timed and density surveys. The summary and conclusion were:

Summary and Conclusions

• 60 salmon fry index timed electrofishing surveys were completed in the Spey mainstem with salmon fry were present in all sites downstream of Spey Dam.
• 82% of the Spey fry index sites, downstream of Spey Dam, were in the moderate to excellent categories.
• Upstream of Spey Dam salmon fry were found at 70% of the survey sites although all in very low or low categories.
• Salmon parr counts during the fry index surveys were down compared to 2013/14 with similar findings in the Spey mainstem density surveys.
• The salmon fry index surveys in the Dulnain found that although the counts were higher than recorded in 2012 there was no significant difference between 2012 and 2015.
• Salmon fry were found in all the Nethy index sites with the normal pattern of declining counts with altitude.
• The salmon fry index counts in the Luineag were in the moderate to good categories at all sites.
• In the Am Beanaidh the distribution of fry was atypical with higher counts found in the middle and upper sites. Channel instability in the lower reaches was highlighted.
• Overall statistically significant increases in densities of salmon, and trout, fry and parr were recorded at the sites surveyed in both 2012 and 2015.
• In the Dulnain density sites salmon and trout fry, and parr, were significantly higher than recorded in 2012.
• Monitoring of habitat restoration sites in the Dulnain catchment highlighted the value of such work, where opportunities exist, with improved fish densities in both diffuse pollution and morphological target areas.
• Annual monitoring of site in the upper Dulnain suggests that spawning stock abundance may limit production in more peripheral areas of the catchment.
• In the Nethy significant increases in salmon and trout fry, and trout parr, were recorded compared to 2012.
• In the Druie monitoring sites there were no significant differences in juvenile salmonid populations compared to 2012.
• In the burns monitoring sites only trout fry densities were significantly higher than recorded in 2012.
• Improved juvenile salmonid populations were recorded where fish passage improvements had been installed in the Mackalea and Broad Burns.
• Monitoring in the Tommore Burn continues to produce positive results with the smolt trap adding additional value and outputs.
• Parr densities recorded in 2015 in some sites were lower than recorded during recent surveys at the same sites however the parr present at these sites were of greater average size, highlighting the plasticity of the salmon lifecycle and their ability to cope with population disturbances.

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Tommore Burn ghillies electrofishing

Last night we enjoyed the company of a group of Spey ghillies who joined us during the monitoring of the stocking carried out in the Tommore Burn last year. Last September the ghillies fin clipped all the parr stocked in the burn therefore providing easy visual recognition of stocked fish.

After meeting at Ballindalloch Jimmy Woods eventually led us to the monitoring sites. We planned to repeat a couple of monitoring sites that we had surveyed in both 2012 and 2013. We set up the stop nets and from the start we caught fish, most of which were salmon parr. The habitat in the Tommore Burn is excellent with moss covered boulders and undercut banks. After we demonstrated the banner net operation the Craigellachie ghillies took control of the fish catching. Despite the banter about their relative, recent, lack of experience in netting fish they did a great job. The gusto with which Dougie Ross took to the task was a revelation; definitely biologist material there!

Steve assisted by the Craigellachie ghillies electrofishing in the Tommore Burn. Chris can even do it standing on one leg.

Steve assisted by the Craigellachie ghillies and Steve Brand electrofishing in the Tommore Burn. Chris can even do it standing on one leg.

The Tommore Burn (a tributary of the Avon) has been stocked upstream of an impassable culvert on the Glenlivet Road. It had been stocked previously in 2012 with salmon fry in June although they were not fin clipped. There was great interest in the fish and it turned out that all were fin clipped. The condition of the fish was very good and they ranged in size from 72mm to 103mm at the first site.

Not the best photo but this is one of the fin clipped fish stocked in 2013

Not the best photo but this is one of the fin clipped fish stocked in 2013

None of the fish stocked in 2012 were found. Judging by the size of the fin clipped fish they are all likely to smolt as two year olds next year. If a parr reaches 90mm in length by the end of the growing season it is considered likely to smolt the following spring. Therefore in the Tommore Burn most of the stocked fish will be big enough to smolt as two year olds.

22 fin clipped parr were found in a stretch of the burn about 30m long in the first site with lower numbers in the second site. We normally find that we catch about 60% of the parr in the first run down a site so the actual parr population present would have been higher. A comparison of the salmon and trout densities in the two sites surveyed are shown below.

TSite SA1b was the first site surveyed. I mentioned last night that the salmon parr density was probably in the excellent category but it didn't quite make that, although good is what it says on the tin.

Site SA1b was the first site surveyed. I mentioned last night that the salmon parr density was probably in the excellent category but it didn’t quite make that, although good is what it says on the tin.

It can be seen that the density of salmon parr at both sites was higher this year than that recorded in 2013. There were quite a lot of salmon parr in the first site but the SFCC classification system for the Moray Firth region is demanding; it takes a lot of parr to make it into the dark green category. The trout parr density has declined in both sites. That is not unusual in stocked sites, the increased competition from the stocked fish often depresses the existing fish population, however experience has shown trout densities can recover quickly in the absence of stocking or even when stocked if environmental conditions favour trout.

All in all it was a very enjoyable evening. As with any type of culture the satisfaction of seeing the results of your efforts in the flesh never diminishes. No doubt every grilse in 2016, and every salmon in 2017 and even 2018 will be examined very carefully for the absence of an adipose fin!

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