Gill damage causes 52.8% mortality at Wester Ross site

“This has been a catastrophic event for Wester Ross, in over 40 years of salmon farming. Our dedicated farmers have never had to manage such severe mortality in a very short period of time,” said Wester Ross managing director Gilpin Bradley in a press release.

“Wester Ross salmon located at the Ardessie Farm were affected by a severe plankton challenge which caused an irreparable damage to the gills in a very short period as the seawater temperatures reached their summer peak causing catastrophic mortality rates of 52.8% at Ardessie Farm Site A and 41.9% at the Ardessie Farm Site B.”

‘Soul-destroying’

Bradley added: “This event was soul-destroying for all our farmers and staff who had been caring of these salmon for over 10 months at the time of the event. Fortunately, the remaining salmon have now been fully recovered and are growing well.

“Year 2018 was a record year for seawater temperatures, causing more plankton issues and reduced oxygen levels at sea. Increasing seawater temperatures during summer months due to global warming will continue to be a major challenge for all sustainable seafood farmers around the world.”

Wester Ross Fisheries is the oldest independently-owned salmon farmer in Scotland, and prides itself on its husbandry. It relies solely on wrasse to keep its fish free of sea lice, uses organic fishmeal and uses a swim-through cage system to avoid handling its fish while they’re growing at sea.

The company produces around 2,000 tonnes of salmon annually, 75% of which is exported. In 2017 turnover jumped by £2.7 million to £16.98m, and net profit increased to £2.8m.

Today’s press release, issued on behalf of Wester Ross by the Scottish Salmon Producers’ Organisation (SSPO), follows the SSPO’s release yesterday of mortality figures for the Scottish farmed salmon sector for August. The figures can be seen here.