Spey mainstem surveys update

admin Latest 12th August 2017mainstem, Spey, surveys, update

After eight days of surveying we finished the Spey mainstem salmon fry index surveys today (below Spey dam at least). We usually leave the sites above Spey Dam for a couple more weeks so the results from there will follow in due course.

53 sites were surveyed although only 51 are reported below. The two other sites are an additional site introduced at Kinchurdy in 2015 and an alternative Aviemore site surveyed for the first time today. The results from the Aviemore site will be discussed below these sites are not presently part of our routine reporting network.

The Spey 2012 - 2016 salmon fry index survey classification scheme and the 2017 salmon fry counts are shown in the tables below.

Spey salmon fry index fry and parr classification scheme (based on 442 Spey surveys completed 2012 to 2016).

Of the 51 surveys only four were not in the good or excellent categories. The two sites in the low category were the perennial low fry count site at Phones and the site closest to Spey Dam.

The mean salmon fry count for sites downstream of Spey Dam in 2017 was 32.5/min, the highest mean count recorded during the six year monitoring period. This situation was not unexpected; there were good numbers of spawning fish in the mainstem last year and flows during the critical incubation period were benign. We have yet to do a mainstem survey, downstream of Spey Dam, where no salmon fry were found, but to find such consistently high numbers is unprecedented. The relatively high abundance of fry at present is readily observed by anyone who takes a few steps along the shallow margins. Fry are only the building blocks but our monitoring shows that high fry counts are usually followed by high parr counts in subsequent years; barring population limiting or regulating, events.

These surveys are primarily to assess the salmon fry population but we also catch parr. In 2016 the parr counts were published in the same format for the first time with similar colour coding based on 20% bands.

We start these surveys in the lower river, working upstream, and during the first day or two parr were notable by their relative absence. As we progressed upriver the parr counts improved with some sites producing their highest parr counts (Ballindalloch through Tulchan in particular). The mean parr count (downstream of Spey Dam) is just below average for the sequence, with the lower river counts probably reflecting the lower fry counts in that part of the river in 2016. The Phones sites may be a low fry count site but it is often above average for parr, as was the case in 2017. We noticed in 2015, another year with low parr counts in the lower river, the fry grew well, well enough that a proportion would reach the size threshold to become a one year old smolt. This is likely to happen again this year, although the future viability of young, and small, smolts is probably not as good as the normal older and larger type.

Most of the sites surveyed are considered to provide good or excellent habitat for fry, but not all. One example of a site where the habitat is categorised as parr in the Aviemore site S195L1. However, despite the poor habitat we still caught 53 salmon fry in three minutes today; even the poor areas of the Spey support decent numbers this year.

S195L1 survey site at Aviemore. The substrate is mainly sand/pebbles with the sampling done in little runs between weedy mounds. (Photo credit Sean Robertson)

There are few suitable run/riffle habitat sites in this part of the river but we did survey a new site today 1,500m further upstream. The habitat here was excellent resulting in a catch of 224 salmon fry, the highest count from any site this year. It is good to see that suitable habitat is being well used as fry produced in these small patches of good habitat will help populate the entire stretch with parr.

The new Aviemore site surveyed today. The substrate and fast, shallow, flows are ideal for salmon fry. The results from this site have been filed but are not presently used as part of the routine monitoring. (Photo credit Sean Robertson)

It was good to complete the mainstem surveys within a relatively short period during a period with consistent low water conditions. Our attentions will now turn to the Avon, and Livet, where we will repeat some of the surveys from last year to see if fry counts have recovered from the low values recorded in the wake of Storm Frank.

Incidentally volunteers are always welcome on these surveys. If you fancy a hard working day out in a beautiful part of the Spey catchment just get in touch.

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Spey salmon fry index mainstem surveys 2017

admin Latest 22nd July 20172017, index, mainstem, Salmon, Spey, surveys

Conditions have been perfect this week for the mainstem salmon fry index surveys, low water being one of the most desirable factors. Therefore we started the 2017 surveys on Monday making good progress reaching as far upstream as Tulchan by the end of play today. The salmon fry index surveys consist of 3 minute timed surveys, primarily in shallow run riffle habitat although for continuity and historical reasons some of the sites are equally suited to parr. We try to do these surveys at the same time of year keeping as many variables as consistent as possible e.g. same sites, staff and equipment.

The draft results to date for salmon fry are shown in the table below (for those not familiar with the colour coding black is absent, red the bottom 20%, followed by amber, yellow, light green, with dark green for the top 20% of Spey results 2012 to 2016)

Spey mainstem salmon fry index results to date. The results from the lower half of the river have been good with all sites in the moderate to excellent categories. The mean salmon fry count from the sites surveyed so far is the highest in the sequence. Tulchan D remains the only site with 100% dark green classification, although the counts were actually below average for that site today, perhaps a consequence of the unusually good parr counts (see below). (Note that the Phones & Lower Pitchroy sites have still to be surveyed)

These initial results are encouraging although not unexpected following an excellent spawning and relatively benign flows overwinter. The 8ft spate in early June does not seem have had too much of an impact; thankfully. A feature this year is the consistency of the results, perhaps this is a consequence of the spate which may have evened out the distribution of the fry from their initial clumped distribution arising from proximity to the redds.

The situation for parr is a bit different with low parr counts in the lower reaches, improving greatly as we progressed upstream.

Spey salmon fry index parr counts. Although these surveys are primarily intended to assess salmon fry parr are also captured. Parr were notable by their relative absence in the lower sites but from Aberlour upstream the results are much better. The salmon parr counts from two of the four Tulchan sites were the best recorded with results from the other two being the second highest. The low parr counts in the lower sites are likely to be a consequence of the low fry counts in the river downstream of the Avon confluence in 2016 - remember Storm Frank?

A sample of the typical mixed catch of fry and parr from the Tulchan, Ballindalloch and Knockando sites today.

The June 2017 spate may not have affected fry counts too severely but large scale riverbed movements were apparent almost everywhere downstream of the Avon. The locations of one or two of the survey sites has to be moved slightly due to the riverbed movements. This is not critical with this type of survey where we follow the habitat rather than fixed landmarks. At other sites the surveys may have been completed in the same location but the habitat had changed due to sediment deposition.

Recent deposits of cobbles in a survey site at Knockando. These fresh looking cobbles are recent arrivals, formerly this site was dominated by boulder habitat, some of which protrude above the new cobbles. It was much easier wading than usual today but these cobbles are likely to move during the next few spates.

It doesn’t take long for nature to colonise empty habitat as can be seen by the number of simuliidae larvae on this recently deposited rock.

Few trout have been recorded so far during these surveys, no surprise as they generally spawn in the tributaries, but there does seem to be more eels than in recent years. In the first two sites elvers were present in abundance with the size distribution increasing quickly as we progressed upstream. The concern regarding low eel numbers in recent years seems to have abated a little, which in my view is a good thing. I like to see everything in the river doing well, well nearly everything! Eels, like salmon, are ocean migrants, and whilst their life cycles are quite different both species depend on the health and suitability of a range of different habitat types.

Ultimately today turned out to be a good day; we made good progress with our surveys, spent some quality time with the new Tulchan factor and ghillies and there were lots of juveniles to be counted. Not bad at all considering I was on the point of going back to bed when I got up this morning. A summer cold is a bind but once I was up and about it was forgotten about. I even did some maintenance on the pick-up tailgate - it shuts now, the old 3 in 1 is great stuff.

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Mainstem electrofishing survey results 2016

admin Latest 27th October 20162016, electrofishing, mainstem, results, survey

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.

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.

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.

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 (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. 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.

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 mainstem analysis: parr size distribution

admin Latest 2nd November 2015analysis, distribution, mainstem, parr, size, Spey

The Spey mainstem is too big for quantitiative electrofishing surveys in the normal manner but last year we re-introduced some of the quadrat surveys with defined areas of the riverbed electrofished semi-quantitatively i.e. single run survey protocol.

This blog post reports on the results from two of the sites, one in Aberlour and the other upstream at Blacksboat.

Site S7 in Aberlour. The area fished is 22m long by 5m. In 2015 ranunculus had made a reappearance, providing cover for fish but making them difficult to extract; as a result we missed quite a few fish, although not enough to significantly alter the results.

Site S9, just upstream of Blasksboat. The dimensions of this site were similar to S7.

Site S9, just upstream of Blacksboat. The dimensions of this site were similar to S7, although just under 20m long. This was a new site a short distance downstream of the site surveyed in 2014 but will be a more suitable site going forward.

The river at the Aberlour site is very stable and there were no significant physical changes since last year other than the reappearance of ranunculus. The surveys were completed within a day of each other, in early Oct in 2014 and 2015.

In 2014 we caught 151 salmon fry and 70 salmon parr at the site in Aberlour whilst in exactly the same area yesterday we caught 110 fry and 28 parr. This is a sigificant reduction in fish densities, certainly for parr especially when considering that the 2014 survey was after the damaging August 2014 Hurricane Bertha spate.

An analysis of the size distribution of the fish shows some interesting differences.

Aberlour site, S7 1st Oct 2014. Of the 70 salmon parr captured 63% were over 90mm and therefore likely to smolt in 2015, the remainder would probably spend another year in the river before smolting in 2016 (if they survive that long).

Aberlour site, S7 2nd Oct 2015. 28 salmon parr but all well above the 90mm smolting threshold.

In 2014 the mean size of the fry was 54mm, whilst on practically the same day in 2015 it was 63mm. The mean size of the 1+ parr in 2014 was 91mm whilst in 2015 it was 114mm ( note that the scales have still to be read for the 2015 samples but aging by size distribution won’t be far out). So there was a much lower density of parr at that site in 2015 but they are all above the smolting size threshold.

The large size of the fry has been a feature of the 2015 surveys even though the summer temperatures were never high and the mean water temperature must have been lower than in 2014. A factor contributing to the bigger fry is probably the lower parr densities. High parr densities would suppress the fry population through predation, harrassment and displacement from the best feeding lies.

The findings at the Blacksboat sites were similar regarding the average sizes of each age class and parr densities, although fry densities were higher here in 2015.

Blacksboat site 1st Oct 2014. Of the 29 parr captured 72% were above the 90mm threshold. (Not sure why the colour coding for age classes didn’t work for this graph when exported from the database)

Blacksboat site 2nd Oct 2015; all the salmon parr were above the 90mm smolting threshold.

The salmon fry at the Blacksboat site were smaller in 2014 than in 2015 (53mm in 2014 and 57mm in 2015), with the 1+ parr 89m in 2014 compared to 103mm in 2015.

All of this highlights the dynamic situation that occurs within any territorial species when population densities or environmental conditions change. Parr densities are down in 2015 but those present are larger with a higher proportion likely to smolt in 2016; partially offsetting any loss in production, and possibly improving subsequent survival.

This could result in a situation whereby in 2016 there are few 2+ parr but a large class of 1+ parr from which the 2017 smolt run will be derived. We intend to maintain these selected semi quantitative mainstem surveys on an annual basis providng the opportunity to monitor these changes in the parr population structure over a longer period.

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Spey mainstem salmon fry surveys 2015

admin Latest 13th September 20152015, mainstem, Salmon, Spey, surveys

It may have been a summer of excellent conditions for angling but the up and down water levels have played havoc with the electrofishing programme, especially in the mainstem. However, with only three sites remaining to do the results are almost complete. It should be noted that the surveys were completed over an extended period this year compared to normal with the median survey date 16 days later than in 2014.

The mainstem salmon fry index surveys comprise 3 minute electrofishing sites, generally in shallow run/riffle with cobble substrate. However, due to habitat distribution and a mix of historic and new locations, the sites cover a range of habitat types. We do this type of survey to try and understand the distribution, and success or otherwise, of salmon spawning along the full length of the Spey mainstem.

Spey mainstem salmon fry index survey 2015. The table is ordered from the bottom of the river to the top with the site code based on 500m sections from the sea. For example Site S264R1, Truim is 132km from the sea.

Th mean number of salmon fry/minute in 2015 was 18.8, exactly the same as recorded in 2014 (it is unlikley that the three remaining sites will alter the average significantly). Considering the low catch of salmon, and the apparent low number of adult fish in the river last year this is a satisfactory result for fry.

After four years of consistent surveying some patterns are emerging;

From Craigellachie downstream the results are generally above average with all sites in the moderate to excellent categories this year.
From Craigellachie to Phones the results are generally lower, no doubt a result of the higher gradient here and the restricted availability of spawning gravel.
The Ballindalloch to Castle Grant area generally supports above average counts although Tulchan D is the only site to be in the excellent category every year.
The two sites in the Grantown Angling Association water were good this year - better than normal
Above Grantown the gradient flattens out and suitable survey sites are less frequent. In suitable sites fry counts are often good e.g. Abernethy AA and Dalraddy. The production of juvenile salmon in this area should not be underestimated, on warm, still, days in the summer many parr can be seen rising in the wide, shallow glides prevelent in this area, and it is not as bereft of spawning gravels as it may appear at first glance.
We introduced a new site this year in the upper river to replace the Truim site which was difficult to access and contained barely enough suitable habitat for 3 minutes surveying. The new site was 2km further downstream with good habitat and is likely to support higher fry counts on average than the site it replaced. Note the lower Badenoch AA site will not be surveyd this year due to access restrictions associated with bridge repairs.
The two sites closest to Spey Dam produced lower counts than usual this year.
Above Spey Dam we found fry at 70% of the sites, a big improvement on the last two years. The fry counts here were all in the very low or low categories so whilst some fish must have made it up to spawn last year the counts suggest the spawning stock above the dam was small.

Water levels were on average higher this year than in the two previous years but the relatively stable results support our previous conclusion that this survey technique is not as sensitive to water levels as it may appear (H&S being an equally important consideration for mainstem surveys).

Whilst some of the survey dates were later than normal we have surveyed some sites later in the past but never have we found mainstem sites where the average size of the fry was over 7omm in August. At the Boat o’Brig site the largest salmon fry were 86mm; a size and date combination with the potential to produce one year old smolts next year.

Why such large fry you may ask as it has certainly not been a year with high water temperatures which would promote growth? The relatively low numbers of parr recorded this year is likely to be a contributing factor, as could the medium water levels with high wetted areas of habitat available. The presence of high densities of larger parr is likely to depress the feeding activity, and therefore growth of, the smaller fry but in years when the parr counts are lower the absence of “despotic behaviour” by the parr could allow more of the new season fry to survive and thrive.

Again we can say that salmon fry were present at every site below Spey Dam. Above Spey Dam the juvenile salmon population continues to be too low and we can only conclude the adult spawning stock in that part of the river is not in a healthy state.

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Tropical storm Bertha aftermath: juvenile stock survey and mainstem stocking monitoring

admin Latest 3rd December 2014aftermath, Bertha, juvenile, mainstem, monitoring, stock, Stocking, storm, survey, Tropical

Trying to assess the impact of extreme spates on our juvenile stocks is a long held ambition and something I promised to do at the Spey Fshery Board AGM two years ago. Big Bertha provided the ideal oportunity with pre event electrofishing survey data available and the low water in September providing ideal conditions for repeat surveys.

The Spey up in amongst the trees on the 11th Aug 2014

The Spey up in the trees on the 11th Aug 2014

For the monitoring strategy we decided to replicate some of the timed surveys in the Spey mainstem and River Fiddich. Eleven timed sites were repeated on the Spey and four in the lower Fiddich. The results were interesting with a statistically significant reduction in the fry counts but an increase (although not significant) in the parr counts. The three Spey mainstem sites with the largest reductions in fry counts were all in areas where the riverbed was liable to become mobilised during the peak of the spate. There was less of a change in the pre and post spate counts in more stable parts of the river.

We found evidence of downstream movement of juvenile fish, something that was particularly evident in the Fiddich where the thermal uplift from the distillery cooling water has unique effects.

The salmon fry numbers overall in the Spey survey sites after the spate were close to the average for the whole Spey in 2014 summer surveys. In the Fiddich the decline was greater although from a higher base level. The study raised as many questons as it answered. For example how many fry would we normally expect to find in September compared to the usual monitoring time of July? I would probably expect to find similar numbers in September as the bulk of the overwinter mortality probably occurs in the autumn onwards.

The perceived wisdom is that although fry numbers are lower now than they would have been if there had been no damaging spate the survival of those remaining should be better due to less competition. We hope that this will be the case although we will have to wait until next years surveys to establish that. The 2015 smolt production will almost certainly be impacted by the big spate and the subsequent fish kill but no doubt nature has its ways of compensating.

Following the Bertha spate a decison was made to stock the 50,000 lower Spey origin hatchery fish back into the lower mainstem rather than into lower river tributaries. We were able to monitor the impacts of this stocking as the stocked fish were adipose fin clipped by the Spey ghillies. The fin clipping allowed us to successfully identify the stocked fish so that their contribution could be assessed.

The results from the stocking monitoring and the post spate monitoring can be read by clicking here.

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Spey mainstem semi-quantitative surveys

admin Latest 6th October 2014mainstem, semiquantitative, Spey, surveys

For our last day electrofishing we headed for the mainstem to collect some semi-quantitative (no stop nets and only one run through with the electrofisher) data on fish densities. Mostly we do timed salmon fry index electrofishing surveys on the mainstem but that techique doesn’t produce data on fish densities. It is impossible to fish the entire width of the Spey mainstem (even in these very low water conditions) so we restricted ourselves to surveying defined areas along the margins, a technique that had been used before and should be repeatable in the future.

The mainstem density site at Aberlour. The site was 5m X 22m long giving an area of 112m2. We found over 150 salmon fry and 70 parr in the area outlined by the red lines. Habitat quality was excellent with mossy boulders and the remnants of ranunculus plants.

This area of the river at Aberlour has in the last couple years produced high salmon and parr counts so it was no surprise to find that densities of both were excellent. The density of salmon fry was 134/100m2 and for parr 62/100m2. Over 60% of the parr were larger than 90mm, a size threshold considered to indicate it would be ready for smoltification the following spring.

The next site had been surveyed before in 2002 and 2003, although the river had changed a little making exact replication difficult.

Mainstem site upstream of Blacksboat. Not an easy site to fish now; it was deep on the outer edge with sandy deposits along the bank. Habitat quality was rated as moderate. However we still caught 85 salmon fry and 29 parr along with a few trout, eels and a minnow. 80% of the parr were large enough to be expected to smolt next year.

The density this year was 98 fry and 33 parr per 100m2 respectively. The salmon fry density was similar compared to 2002 (114/100m2) and 2003 (79/100m2) whilst the parr density was higher than found in 2002 (20.2/100m2) but less than the 50/100m2 recorded in 2003. Still there appears to have been little overall change in fish densities now compared to that snapshot from over a decade ago.

The next site was upstream of Advie Bridge where the habitat looked good but fish densities were lower than anticipated. I don’t have a good photo showing the entire site but the picture below shows the type of habitat present.

Lower half of the mainstem site at Advie Bridge. We caught 15 salmon fry and 7 parr from an incomplete site of 73m2. Lower than expected but still moderate in the SFCC classificaton for a stream over 9m wide. 70% of the parr at this site were big enough to smolt in 2015 (if they survive).

Unfortunately two thirds of the way through the site Steve slipped on the slimy rocks, landing on the anode which ceased to function. Thankfully he was okay and it was the the last electrofishing day rather than in the middle of our survey programme. We missed out on the last planned site at Grantown but we had at least gathered some interesting semi-quantitative data from the mainstem, the most important part of the Spey catchment in terms of smolt production.

Spey biologist with obligatory clipboard!

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Mainstem sampling: Days 1 & 2

admin Latest 16th July 2014days, mainstem, sampling

Well after Friday’s very hot weather, today was considerably damper. Never the less, we pressed on with our mainstem sites, making it up as far as Easter Elchies, missing out a couple of beats which we will return to at a later point.

On Friday, we completed the first 5 sites, which are all on the Brae Water beats. The first site was close to the Essil pool. This site is our closest to the sea, and last year we found Flounders, which use the river as a juvenile nursery. This year we found no flounders, but we did find minnows which was surprising as they usually live in still water, but this was very fast flowing. We had 49 fry and 7 parr this year in contrast to 68 fry and 13 parr last year which was disappointing. The next site up was by the Quarry pool, where we had one more fry than last year (52) and no parr which was one less than last year; fairly consistent results. At Brae Beat 5, we have a site close to the ghillies hut. It’s always nice to catch up with the ghillie and anglers, who were beginning to arrive for a sunny lunch. Unfortunately this site produced 74 fry and 2 parr in contrast to 158 fry and 7 parr last year. This is not a decline we want to see! The river is so mobile down there, and we did note that the habitat had changed significantly since last year; it was the ideal habitat for fry with lots of pebbles and gravel but this year it was dominated by boulders and cobbles. It is possible that this contributed to the decline we saw, the salmon don’t always spawn in the same place, they pick the best habitat available to them, as do the fry when they emerge. So the fry could’ve just been focused in a different area. There was a similar decline in fry at the next site, with 86 this year in comparison to 173 last year. The numbers of parr here though had gone up from 3 last year to 12 this year, demonstrating that the habitat was more suited to the parr this year than fry. Our final site of the day was fairly similar regarding fry, with 69 fry this year and 72 last. The number of parr has gone from 8 to 4.

Today we started at Delfur, with our site just upstream of Boat O’Brig being the first one, and was a really positive start to our week! The number of fry had increased from 36 to 165 which was great to see. The parr had also doubled to 12. The next site had a lot of expectation after being our best site of the mainstem surveys last year with 270 fry. It couldn’t quite match that number today with 198 fry, however this is still a lot of fry in three minutes and our effort of fishing was seriously hampered by the troublesome ranunculus. There is no doubt that this plant provides cover for fish, but when you try to electrofish it the fish often get stuck in it or manage to dodge the net due to it preventing a tight seal on the bottom of the river. Once we got out of the ranunculus filled area, we caught plenty of fish. The buckets of fish looked fairly impressive when we took them to be processed, the bottom of the bucket isn’t showing much!

Catch of fish at the first Delfur site

The next site on Delfur consisted mainly of boulders and cobbles, making it very tricky wading. We caught 40 fry, just two less than 2013, and 11 parr in comparison to 8 last year. We also caught one salmon with a rather large kink in it’s tail. It was managing to swim fairly well, and had made it this far! However this would make it potentially more vulnerable to predation, and less able to catch food.

A fairly obvius deformity in this salmon's tail; it was slightly smaller than some of the other fry we caught but it had developed a unique swimming method!

A fairly obvious deformity in this salmon’s tail; it was slightly smaller than some of the other fry we caught but it had developed a unique swimming method!

After leaving Delfur, we moved up to the two Rothes sites. The first was at the Gaintree pool, where last year we had 132 fry and 21 parr, but unfortunately today we only caught 31 fry and 5 parr. Similar to other sites, the habitat was filled with boulders, the opposite to the gravel fry like, and the ranunculus also posed a problem. Never the less, still a disappointing result. The second site was at the Creachies pool, this one was much better, with 27 fry and 47 parr in comparison to last year’s result of 28 fry and 36 parr. The parr here were particularly dark in colour, they almost looked mature which seems a bit early on in the year. Salmon are incredibly talented at changing their colours to match their surroundings though, so it is possible that this was a response to dark water and substrate.

Six very healthy parr from Rothes. They are fairly dark in colour, perhaps in repsonse to their surroundings.

The final site today was at Easter Elchies, which we were pleased to be joined on by the ghillie and one of his guests who was interested in what we were doing. We always enjoy demonstrating what we do to people fishing on the river, and it is often the case that they are amazed at what emerges out of such a small area! We were pleased to be able to catch 131 fry and 3 parr, and even happier to be able to report to the angler that this had increased from 104 fry and no parr last year.

So the first two days have been fairly mixed to say the least. But with 11 sites down and 53 still to go, it is early days and we look forward to having a completed picture. I also need to look at 2012 results to see how these sites compare over the three years surveying. Watch this space!

Spey Fishery Board