Smolts

A 4ft rotary screw trap (RST) was installed and operated on the River Truim, an upper tributary of the Spey during 2010. Data on the run time and age structure was collected for salmon smolts and compared with environmental factors including flow and temperature. A salmon smolt output for the river was estimated using mark recapture approach. Data on migratory trout and other fish species was also gathered.

A rotary screw trap (RST) was installed in the River Tromie, an upper tributary of the River Spey during 2009 and 2010. Salmon smolts migratory trout and other species were captured. A simple dye mark and recapture  technique was used to determine trap efficincy and provide an estimate of salmon smolt output.  Data on the run time and age structure was determined and compared with environmental factors including flow and temperature.

R. Laughton, S. Burns, J. Reid and R. Miele: 2008

Two 6ft rotary screw traps were operated on lower mainstem Spey during 2008. Data on the run time and age structure was determined along with the effects of environmental parameters such as water flow and temperature. Smolt output estimates were derived using mark and recapture techniques and mathematical models. 

R. Laughton, S. Burns and J. Reid: 2008

Two rotary screw traps were installed on the mainstem Spey and proved to be powerful sampling tools for salmonid smolt populations. Data on the run time and age structure was determined along with the effects of environmental parameters such as water flow and temperature. Initial application of mathematical models allowed population estimates to be created although there is still a considerable amount of work to do to refine this approach. The RSTs provided excellent data for salmon smolts and although trout smolts were regularly caught the traps it did not appear to be as good at trapping them. Data on other fish species was also collected.

A 4ft rotary screw trap (RST) was re-installed on the River Truim, an upper tributary of the Spey during 2011. Data on the run time and age structure was collected for salmon smolts and compared data from 2010 and environmental factors including flow and temperature. A salmon smolt output for the river was estimated using mark recapture approach. Data on migratory trout and other fish species was also gathered.