A Scottish salmon farm lost more than 52,000 juvenile fish in a "major" seal attack on 31 December, it has emerged.
During the incident seals ripped open nets and killed "many" fish, while others escaped, according to an industry body.
It occurred at a farm based at Portree on Skye managed by The Scottish Salmon Company (SSC).
The business was due to have new anti-predator netting technology installed by the end of this month.
An SSC spokesman said: "Our Portree site has recently been subject to persistent attacks from a large group of seals which, despite our best efforts, caused significant damage to one of our nets.
"Our staff moved quickly to repair this damage but unfortunately a number of fish escaped.
"All the members of our team at Portree are extremely disappointed, particularly given they have worked so diligently to maintain an excellent containment record at the site."
The company added it was now working closely with the local fisheries trust to record any sightings and recapture stock wherever possible.
The Scottish Salmon Producers Organisation (SSPO) said predation attacks continued to have a significant impact on fish health and welfare.
It reported that more than 500,000 Scottish farmed salmon died as a result of seal attacks over the year to May 2020.
The fish died either from a physical attack or "indirectly from stress".
SSPO chief executive Tavish Scott said: "Salmon farms and seals can co-exist quite happily in the marine environment.
"Seals can, however, inflict vicious and widespread damage on salmon farms, killing significant numbers of fish in each attack.
"This distressing incident shows that our farmers need access to a range of effective tools and measures to deter seal attacks and protect their livestock.
The organisation said recent legislation had reduced the methods available to fish farmers to manage the problem, including a ban on the use of "lethal controls", a change which will come into effect in full at the end of January.
It added: "The SSPO continues to call for Scotland's salmon farmers to have full access to all available effective non-lethal measures if they are to fulfil their statutory duty to protect their fish."