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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Source: Spey Fishery Board – Spey 2016 electrofishing report