Average female lice per fish

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Salmon Scotland mortality

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Cumulative mortality over full production cycle

Sgian Dubh Production cycle end date: Oct 2018
Total losses: 16.3 %

Sgian Dubh Production cycle end date: Sep 2020
Total losses: 39.4 %

Sgian Dubh Production cycle end date: Aug 2022
Total losses: 7.5 %

Sgian Dubh Production cycle end date: Jun 2024
Total losses: 32.9 %

Sgian Dubh Production cycle end date: Aug 2026
Total losses: 50.9 %

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Inspection reports

Case Number: 2020-0342

Download Mortality information (last 4 weeks)
Week 33 - 102344 - 39.55%
Week 32 - 11582 - 2.12%
Week 31 - 5107 - 1.46%
Week 30 - 7464 - 1.82%
Week 49 (2019) - 13048 - 1.58%
Week 46 (2019) - 15895 - 1.76%
Sgian dbhu has been one of the worst affected sites in loch striven due to historic levels of PD and AGD levels, higher biomass may have exacerbated effects of environmental insult, site is also closest to the freshwater run off and therefore would have been the most exposed to suspended solids in the loch after the extreme recent downpour.
Dinoflagellate combined with solids in water after heavy rainfall resulted in environmental insult. Mortality is now back at normal levels and appetite are doing well.
Fish have been doing really well but have succumbed to an environmental insult caused by a multitude of factors in the loch.
Environmental event lasted only a few days and mortality levels are back to normal. Harvesting procedures have commenced and fallow is expected within the month. Environmental insult combined with historic PGD is thought to have been the main source of high mortality. [Original PDF]

Case Number: 2021-0245

Download Fished sampled for VMD looked in good condition. Fish were feeding very deep.
Water temperature was found to be above 14 degrees Celsius. So full ECI could not be completed. Case type changed to
REG [Original PDF]

Case Number: 2021-0451

Download Inspection conducted by , observed by .
The main population looked healthy, feeding deep in the water column. One dead fish and a small number of lethargic fish observed. One moribund seen in pen 8 and taken out for diagnostic sampling.
The site has been inspected on the 15/07/2021 but the water temperature was found to be above 14 degrees Celsius. So full
ECI could not be completed. Case type changed to REG, CNI, SLI. Biosecurity, containment and sea lice records were found to be adequately maintained and therefore they have not been inspected again. [Original PDF]

Case Number: 2023-0460

Download Salmon came march this year, wrasse in June
Stock on site have come from - Applecross, Kinlochmoidart, Harris Lochs, Hebridean Smolt (Clachen Hatchery) and
Couldoran - Most stock are native Hebridian.
Wrasse mortalities - Wk38 - 2.48% (1,321), Wk37 - 2.92% (1,600), Wk36 - 2.98% (1,470), Wk35 - 2.88% (1,250). Wrasse mortality attributed to environmental reasons - jellyfish, possible pollution from forestry upstream (wrasse don't like suspended solids in the water).
Freshwater treatments last week and the rest of the site is being treated tonight.
Latest health report - systemic bacterial infection. Furunculosis, suspected Tenacibaculum sp., mixed gill infections with AGD,
Branchiomonas-like epitheliocysts and lamellar pathology suspicious of infection with Desmozoon lepeophtherii. Waterborne environmental damage to gills - possibly jellyfish or stinging cell contact.
Health team including head vet are on site today to collect samples for general health screening.
Sealice - SLICE was a precautionary measure.
During physical inspection of the site, 4 out of 16 pens had a couple of mortalities observed on the surface of the water. No moribund fish were observed on site. A handful of lethargic fish were observed across the whole site but when approached all fish swam off quickly. Water visibility on site was poor due to the large volume of freshwater input from the recent wet weather.
Fish that were observed were shoaling a few feet below the water surface.
Fish for VMD samples were collected from pens 1, 4 and 10. Fish sampled for VMD appeared healthy both externally and internally with no lice observed on any fish collected. [Original PDF]

Case Number: 2025-0426

Download No cleanerfish on site.
Site will start ensiling waste soon once ensiler has been set up.
Mortality since the last inspection has been low, below reporting threshold for the last cycle and this cycle (after 2 weeks initial input) until Wk 43 due to AGD gill issues. Fish were treated with freshwater 1/11/2025. At time of inspection mortality for the current week was well below 1%.
Treatments: This cycle - freshwater treatment for AGD 01/11/2025 all cages and 7 day SLICE treatment 1st-7th September
2025. Last cycle - 2 freshwater treatments from October 2023 until the site fallowed in June 2024.
Health Surveillance: 18/09/2025 (External) - No lice seen, gills look good. Last internal company biology report 27/10/2025 - high AGD visible in most gills checked. Liver lesions on the morts are suggestive of possible pathological/environmental insult.
During physical inspection of the site water visibility was poor due to heavy freshwater runoff creating brackish water. One lethargic fish was observed but it swam off when approached. One pen was observed feeding and fish had a good feed response.
No lice were found during the lice count observation but around a quarter of the fish sampled had a low score for AGD. [Original PDF]

Case Number: 2026-0075

Download Freshwater treatment conducted on site (synchronous with other sites in area) due to the increase in gill scores. The conditions of the gills on site have reportedly improved significantly since the treatment.
In each cage 1-2 fish with lesions consistent of infection with Moritella viscosa (aka winter sores) were observed. These fish were not moribund.
Withdrawal period for TMS set at 21 days as the fish are destined for the US market. In the US 21 days is set at standard quarantine period for salmon set by FDA. [Original PDF]

Case Number: 2026-0156

Download Site visited following notification from the operator of mortality in excess of notifiable threshold.
Freshwater treatment conducted (no FLS). Three hour treatment. The treatment was conducted due to AGD scores on the rise. Traffic light alert system used to warn site manager and health staff about disease challenges on site. Site was on amber for AGD which would not usually trigger a treatment, but, due to other issues, a decision was made to treat before it got worse.
Only treatment since last visit was from 30/04/26 to 05/05/26. All cages treated for 3 hours using freshwater.
Biologist report on 12/05/2026: significant gill pathology noted despite FW treatment. Large proportion of lamellae swollen and discoloured. Moritella lesions observed although thought to be fewer than previously and some with signs of healing. Feed response described as "excellent" during the biologist visit. Salmon gill pox virus, microsporidia, branchiomonas, Moritella, and
PRV all confirmed on site. The presence of ERM was thought possible due to presence of "petechial spotting" on the pyloric caeca, although ERM was not tested for.
Director of health visit on 27/04/26: Functional feed being fed (Algium and DERMIC), to encourage lesion healing and improve health. Note on report "strongly recommend monthly discussions around the future of these fish, as they have had an incredibly challenging start to life".
Estimated to be about 40-50 moribund fish per cage, about 20-30 of these moribund fish displayed lesions associated with an infection with Moritella viscosa (aka winter sores).
No movements of live fish off the site since the last inspection. [Original PDF]

Case Number: 2026-0261

Download First input from Glenfinnan August 2025 - Stofnfiskur stock. No cleanerfish on site.
Currently business is only able to harvest 20,000 per lift - hoping to conduct 3/4 lifts per week. Harvest through the station at
Striven Shorebase, then transported to Cairndow.
Timeline of health issues on site: SRS was detected after input in August 2025. AGD then was detected soon after, which meant there was a requirement to treat the site (FW). Fish were then found to be positive for PRV and SRS detection continued. A couple of FW treatments occurred at the beginning of 2026 following AGD continuing to be an issue; 4 freshwater treatments conducted in total during cycle with last one occurring in wk18. Subsequently, Moritella, PRV and Mycobacterium were detected, with an increase in mortalities observed in March 2026, attributed to these diseases. Functional feed was given to the fish in April 2026 - Algimun as well as C3COS given previously in cycle. High levels of Branchiomonas sp., salmon gillpox virus, Microsporidia in May 2026. Furunculosis has also been recently detected. Health surveillance from the business has been conducted every two weeks and site has had visits from Faroese vet in April 2026 in addition to the in-house vet.
Exophiala sp. - marine fungus also observed in health surveillance conducted by the business.
Due to continuous health issues occurring on site, a sub population of fish were moved to Ardyne (wk 24) to promote recovery.
FW treatments have been managed in such a way that pens with highest morts are treated last to ensure a more biosecure approach to the treatment process.
Health reports reviewed: 18/06/2026 (sampled moribunds and morts, positive for all the above mentioned in 'Timeline of health issues on site'). On 02/06/2026, fin splits observed across all the population and size ranges. Furunculosis has been observed and had screened positive, high levels of complex gill pathogens. On 12/05/2026, histology report showed hyperplasia and complex gill disease.
Sgian Dubh - fallow from June 2024 and August 2025. Plans to rotate the fallow periods in Striven.
Other peaks in 2026 mortality: mortality % and count: Wk14 to Wk27 - increased and peaked at 3.44% WK 22; then decreased and Wk24, 1.77%. Wk25 to Wk28 - weekly at 10 .37 to 12.85%. Wk 28 so far is 2.44%, with predicted mortality to be ~3%.
Evidence of recent increased mortality: pen 3, pen 12, pen 14, pen 15 (total % was 61.66 of total population ) - highest mortality, peaked in Wk26 - harvested out already.
During the site visit, pen 16 and pen 1 were inspected. A few lethargic fish observed. 3 fish removed from pen 16 (planned to be harvested w/b 13/07/2026) and 2 from pen 1. All fish removed were lethargic. These fish were sampled for diagnostics.
Generally, few moribunds were observed across the pens. It was evident that some lesions were present on the fish in the general population but these had been observed to have healed. A few of the lethargic fish were observed with exophalmia.
The site inspection was conducted alongside APHA who conducted a welfare inspection. [Original PDF]

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