The 2011 lamprey survey of the River Spey (Watt et al. 2011) comprised a total of 30 sampling sites, with 24 on the mainstem Spey and six spread amongst three tributaries (R. Fiddich, R. Avon and R. Dulnain). Petromyzon marinus (hereafter referred to as sea lamprey) larvae were only encountered at mainstem sites downstream from Boat of Garten, despite additional sampling effort upstream in suitable habitats where there were abundant Lampetra larvae. In the lower section of the Spey mainstem, sea lamprey larvae were present at 13 of the 17 sites including both the uppermost (Boat of Garten: S17) and lowermost (Garmouth: S1).
The results of this investigation suggest that the distribution of sea lamprey spawning activity and larval occupancy in 2011 within the River Spey SAC was limited to the mainstem downstream of Boat of Garten. No physical barrier for sea lamprey migration has been identified immediately upstream from Boat of Garten, so specific reasons for this upper spatial limit in species distribution can only be inferred. Historical information presented in the 2011 report suggests that the spatial range of sea lamprey previously extended at least as far upstream as Kingussie.
This quote is being provided to SNH for the supply of a sea lamprey Site Condition Monitoring programme for the River Spey in 2018. It is provided to SNH by the University of Stirling, but is a joint bid between the University of Stirling (Colin Bull) and Waterside Ecology (Jon Watt).