Rising sea temperatures have been blamed for a huge increase in annual costs, including the loss of fish worth £7.75milion, at salmon farms operated by Marine Harvest (Scotland).
The firm, part of Norwegian fish farming giant Marine Harvest, said “fish health challenges” and treatment losses during 2014 were impacted by a slight increase in water temperature.
The health issues related mainly to sea-lice, algae and amoebic gill disease – all of which can be exacerbated by the smallest changes in temperature and be ruinous for salmon production.
Marine Harvest’s Scottish arm said its biological challenges were the main factor in increases across a number of cost categories.
These included its annual losses from dead fish, which in 2014 amounted to £7.75million after a £1.9million write-down the year before.
Accounts released by Companies House yesterday also showed Marine Harvest (Scotland) suffered a large drop in pre-tax profits last year to £41.1million, from £62.3million previously.
Turnover for continuing operations during the latest period totalled £218.6million, up from £216.5million in 2013.
The subsidiary highlighted sales costs of £156.4million in 2014, an increase from £132.4million the year before.
An average of 578 people worked for the business last year, up fro 495 in 2013.
Marine Harvest is one of the world’s biggest seafood companies, accounting for between 25 and 30% of the global salmon and trout market.
The Oslo and New York-listed company employs nearly 12,000 people across operations in 23 countries.
In August, group results showed fish escapes and sea-lice cost the Scottish business nearly £240,000 during the second quarter of 2015.
Marine Harvest said its Scottish sites delivered about £5.3million of operational earnings before interest and taxes (ebit) during the three months to June 30, which was down from more than £17.5million a year earlier.
Across the group operational ebit totalled £56.5million – down from £95.8million a year earlier – on revenue that was flat at £517million.