Scottish salmon producers publish monthly mortality rates
Monthly mortality rates at all of Scotland's salmon farms have been published for the first time.
The move by salmon producers follows criticism from a Holyrood committee earlier this year that fish mortality was at "unacceptable levels".
The SSPO data showed the average death rate across all Scottish salmon farms was between about 1% and 1.5% for each of the first four months of this year.
About 60% of farms stocked with fish had less than 1% mortality.
The worst monthly mortality rate, of 19%, was recorded in March at Marine Harvest's Carradale North operation in Argyll, with storms cited as a factor.
Figures for deaths over the full production cycle - which is normally two years - were also released.
They showed that the Scottish Salmon Company lost 58% of its fish at its farm at Inch Kenneth off Mull, where parasitic sea lice had been a problem.
The reporting includes information on the causes of mortality, including gill health, anaemia, marine predators and severe weather.
In March, Holyrood's environment committee warned that Scotland's marine ecosystem faced "irrecoverable damage" from salmon farming if environmental concerns were not addressed,
A report concluded that there has been little progress in tackling environmental problems since 2002.
'Hugely important'
The Scottish Salmon Producers Organisation (SSPO) has insisted that it is committed to long-term sustainability.
Chief executive Julie Hesketh-Laird said: "The health and welfare of salmon is hugely important to salmon farmers.
"This regular, voluntary publication is unparalleled and sets a precedent for transparency in business reporting.
"It sets a base line to show future trends and currently around two-thirds of active salmon farms have 99% survival rates."
The Scottish government's chief veterinary officer, Sheila Voas, said: "We welcome the fact that salmon farming is taking steps to be more open and transparent about the levels of mortality within the sector."