Sea lamprey distribution and abundance in the River Spey: phases II and III, 2001/2002

A quantitative survey of ammocoete abundance was undertaken between Grantown-on-Spey and Aviemore. Sampling further upstream was curtailed due to poor weather conditions and high flow levels. Two sea lamprey ammocoetes were found at a single site near Boat of Garten. Historical data suggests that some sea lamprey spawning behaviour occurs in the River Spey upstream of Grantown-on-Spey, although sea lamprey are more commonly observed downstream of the present survey area. No density estimates were calculated from the sea lamprey catch since these ammocoetes were caught outside of quadrat sampling. Report 043: A walk survey of the River Spey was conducted during summer 2002 to identify potential areas of lamprey habitat. These were then classified into optimal and sub-optimal habitat. In total 158 potential areas were identified, 59 of optimal habitat and 99 of sub-optimal habitat. An electro-fishing survey was then conducted at 28 sites (23 optimal habitat and five sub-optimal habitat) using pulsed DC. Timed fishings were conducted at each site providing Catch Per Unit Effort (CPUE) data. In addition, an estimate of the area fished was also recorded allowing density to be calculated.