The Tay Foundation is a Charitable Trust helping the River Tay and its tributaries, fish and environment
The Big Challenge...
The Tay Foundation is looking for a major sponsor who can help us develop the river system to its full potential over a ten year period.
Juvenile Population Survey (1999-2009)
One of the most practical ways of assessing the health of populations of river fish such as salmon or trout is to monitor numbers of juveniles using electrofishing.
Electrofishing data in itself is not necessarily that informative unless it can be put into context in terms of how many fish a healthy river ought to hold.
One way of doing this is by monitoring individual sites year on year for many years so that trends in population abundance can be detected.
The Tay District Salmon Fisheries Board have in fact surveyed a number of tributaries annually for a number of years, in some instances since 1999. In 2009 the Tay Foundation commissioned the TDSFB to analyse and present the findings of these surveys.
Te report makes fascinating reading and can be accessed through the link below. On the whole it found that in most tributaries, while there is variation in juvenile salmon numbers from year to year, it is clear that while it might not be possible to conclude they are at full carrying capacity they are certainly not "grossly understocked".
However, there were a few places which were clearly understocked but in such cases factors like limited access for adult spawners seemed to be responsible. Stocking with eggs and fry in such instances was shown to successfully increase juvenile salmon numbers.
Electrofishing is the only effective method of assessing the standing stock of juvenile salmon and trout in tributaries of the Tay.