Today we continued with our salmon fry index surveys up the Fiddich. The first site of the day turned out to be the best we have ever done with over 500 fish caught in the three minute survey. The catch comprised 389 salmon fry, 40 salmon parr, 67 trout fry and 5 trout parr. This one we did manage to record on video and it makes pretty impressive viewing. It takes a bit of time to upload and prepare these videos but we will get it online as soon as possible.
It was interesting to note that the average size of the fry at this site was 48.5mm; well down on yesterday’s sites where the fry averaged over 60mm. The difference almost certainly due to the absence of the temperature uplift arising from the distillery cooling water discharges.
The next site was also very good with 316 salmon fry and 70 trout fry. The Fiddich had produced the top three timed survey sites over the last three years.
The catch decreased in the next two sites, although still good with 59 salmon parr caught in one site a short distance downstream of Bridgehaugh where the Cabrach road crosses the Fiddich.
Above the road bridge we did a further four timed sites. The next two sites had a lot of bedrock substrate and fry number were lower although parr were good. The Fiddich was much smaller in size at the two upper sites surveyed this afternoon but we caught a surprising amount of salmon. 42 fry and 38 parr in the upper site of the day was very good in a relatively small watercourse which was verging on being more suitable for trout.
The last site of the day. Really nice instream habitat for juvenile salmon here.
We still have 4 more timed sites to do on the Fiddich plus some density sites but the last two days have really highlighted the productivity of the Fiddich as a salmon nursery area. I have carried out timed surveys in many different rivers and the Fiddich has been the best of all. The secret of its succcess is in the geology of the catchment and the high quality of its water. The presence of limestone results in a relatively high pH for the Spey. The pH of the Fiddich is consistently over 7, sometimes as high as 8, providing productive feeding. Long may it continue.