Scottish Sea Farms is leading a second applied research project on increasing understanding of gill health in farmed salmon with BioMar, the University of Aberdeen and the Scottish Aquaculture Innovation Centre (SAIC).

Scottish Sea Farms’ Head of Fish Health, Dr Ralph Bickerdike, said: “The gills are hugely important to the overall health and wellbeing of Atlantic salmon, yet the factors affecting these vital organs are as highly complex as they are little understood. This second gill health project seeks to explore further the early insights gleaned in our initial collaboration, helping increase knowledge of the key risks and how to pre-empt and avoid them.”
The project team will focus efforts on two key outcomes:
Exploring the effect of geography and seasonal influences on gill health, in order that additional preventative and continuous measures can be identified and deployed
Testing the accuracy of a range of new biomarkers; a suite of veterinary tests which help indicate the health status of fish and will enable more informed decisions.

The insights gleaned won’t just benefit farmed fish in the care of Scottish Sea Farms. SAIC Aquaculture Innovation Manager for the gill health project, Caroline Griffin, explained: “Gill health has become one of the biggest challenges facing salmon production – not only in Scotland, but in Norway and internationally. SAIC is supporting a range of projects across Scotland, drawing on the expertise in our academic institutions and industry to understand the issue and develop innovative solutions. The new knowledge gained will be shared across the sector, helping salmon farmers to maintain healthy populations of farmed fish.”
Testament to just how devastating gill-related challenges can be to fish health, Scottish Sea Farms’ Lismore North farm in Loch Linnhe experienced unusually high mortalities of 22% during the last crop as a direct result of complex gill health disorder.

Said Bickerdike: “When seawater temperature rises, even by something as seemingly slight as 0.5 degrees, more marine organisms grow. In the summer of 2018 – the joint hottest summer on record for the UK – we experienced a phytoplankton bloom in the Loch Linnhe area which resulted in a challenge to gill health. Increasing our understanding of what more we can do to pre-empt and prevent these kinds of challenges is a priority.”