Average female lice per fish

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Salmon Scotland mortality

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Cumulative mortality over full production cycle

East Tarbert Bay Production cycle end date: Jan 2018
Total losses: 14.7 %

East Tarbert Bay Production cycle end date: Dec 2019
Total losses: 16.4 %

East Tarbert Bay Production cycle end date: Jan 2021
Total losses: 11.7 %

East Tarbert Bay Production cycle end date: Jan 2022
Total losses: 80.2 %

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Inspection reports

Case Number: 2021-0146

Download Case paperwork and physical inspection carried out by while shadowed by
Fish removed from pens for vmd sampling appeared in good health with no internal signs of disease. Fins showing no damage. Lice loads reflecting the numbers that have been reported. Site has just begun feeding stock with SLICE.
LUM morts - wk16 326 (0.04%), wk17 533 (0.65%), wk 18 496 (0.61%), wk 19 (706 (0.88%). LUM stocked on site from wk 12.
Seal Pro nets with sinker tube to maintain tension. [Original PDF]

Case Number: 2021-0406

Download All salmon input from Geisgil. Transported in FW. Lump fish input from Ocean Matters and Otterferry,
Morts/site/wk; Wk30 0.32%, Wk31 0.9%, Wk32 1.85%, Wk33 1.07%, Wk34 0.96%, wk35 1.19 %, Wk36 1.3%, Wk37 1.4%, wk38 10.84%, Wk39 20%, Wk40 14.5%, Wk 41 0.95% - part week.
Currently divers are removing about 200 morts/cage/day.
There were a number of mortality disposal methods available for the two sites;
• Billy Bowie- whole in skips to Barkip Biogas (collection docs observed).
• Gogar – Energen Bio Gas- to Dunnswood Road, Cumbernauld (collection docs observed).
• They have a new well boat the Buccaness - hydrolicer and macerator/ensiler. Can hold 1000 cube of morts, current morts on- board of 200 cube. - material ensiled with formic acid. Then it will be pumped off into tankers and used as biofuel but uncertain currently of final destination. The boat was present during our visit.
• Fergusons boat for mort removal had been used but was not on site during our visit.
Collection docs were available for inspection from Billy Bowie and Gogar. Capacity for mort disposal was in my opinion adequate and staff numbers at the sites were increased to deal with the mortalities with staff being brought in from other areas. Divers were also present at the time of our visit for mortality removal.
Lice; caligus peaked wk37 at 10.37. Increased mortality had prevented treatment and there was evidence on site of lice damage on some fish.
Treatments;Hydrolicer 24/6/21- 2/6/21, FW and salmosan 18/7/21-23/7/21, hydrolicer 4/8-14/8, salmosan 28/8, hydroliced 1/9-
4/9, hydrolicer 27/9/-4/10, FW panned 13/10/21.
Health surveillance;
AGD- low level. Most resent sample slight higher but not at levels which would be considered to have caused mortality.
PCV - haematocrit levels. Have fallen in last couple of weeks.
CPK -muscle fatigue for PD- have been low levels showing recovery from infection.
Mortality considered to be due to environmental insult but no jellies observed in water samples. Upwell species were observed.
Morts - normally taken by site boat and skipped at shore base. Divers in daily to remove morts. - numbers of fish on site will be reviewed following a fw well boat treatment. [Original PDF]

Case Number: 2022-0342

Download Fish were input on site for the first time in wk17. Fish were input at ~150g and were noted to be soft as well as possess reduced amount of mucus. The stock on site originates from two hatcheries: Applecross Smolt unit and Girlsta Hatchery. The fish from Girlsta are a mix of stofinfiskur and Aquagen.
During the site inspection, fish were observed to be jumpy. In addition, a freshwater treatment and transfer was occuring to reduce the biomass on site so that in the next 3 weeks a SLICE treatment can occur. The freshwater treatment was being administered by the Ronjafisk and exposure to freshwater is ~1 hour. Transfers were to Druimyeon Bay, where 5 pens from
East Tarbert Bay had already been moved to.
From health surveillance conducted on site, 2 pens (1 and 7) were confirmed to have PRV. No clinical changes were observed and is currently not the primary suggested cause of increased mortality on site.
Caligus levels extremely high in Wk 29, 30 and 31. Micro jelly bloom occurred in the week of input, which agitated gills primarily. Then the arrival of Lion's mane jellyfish exacerbated gill issues on site further. Mild AGD observed in gills of fish.
Diagnostic samples taken from pen 1. Sampled fish were moribund and lethargic. In addition, signs of loss of equilibrium where beginning.
Fish sampled for VMD appeared healthy. [Original PDF]

Case Number: 2022-0465

Download Site visited 17/8/22 and diagnostic samples taken case 20220342. Identified from samples - AGD, IPN, vibrio, aeromonas spp,
Paranucleospora theridion. - PD confirmed onsite along with gill health issues, AGD confirmed onsite.
Weekly morts for site; 19/9 1.21% 7307 fish; 26/9 4.06% 24260 fish; 3/10 10.27% 58941 fish; 10/10 12.85% 66.587 fish; 17/10
8.37% 38559 fish. Freshwater treatment scheduled week 44 - gill health and viral disease.
Morts for week 43 2022 were 48635 fish (11.53%) due to gill issues, PD and rickettsia, week 44 (10.45%), and week 45
(11.89%)
Site thermometer used as error in T146
SLICE treatment 11/9/22; Freshwater on Ronjafisk, 15/9, 11/10, 6/11
Histo health reports; 24/10/22 acute SAV, gills with multiple aetiologies- no amoebae; 18/10/22; gills low level environmental, suspect PRV, low energy stores suggesting fish not feeding. 26/9/22 AGD
Wrasse mortality reported to be low.
Due to poor weather only able to walk round 4 cages. However moribund fish were collected from theses cages. [Original PDF]

Case Number: 2024-0182

Download During previous cycle site had black losses of wrasse at harvest (wk 11 2023, mort count - 12,000)
Before site became fallow the site had experienced elevated mortalities that were mainly contributed to Pancreas disease.
Inspection was conducted by supervised by [Original PDF]

Case Number: 2025-0425

Download Mortality: No reported mortality events since 13/03/2023 (5 weekly, 4.05% due to PD). Wk 35 2025 (25th-31st August): 21%
(only 21 fish). At the time of this mortality, this was the last batch of fish before the current stock. East Tarbert Bay had transferred all fish on site in pen 1 (27,120) to Druimyeon Bay (FS0336), starting on the 23/08/2025. After all transfers were completed, when lifting the pen net on the 25th August, 21 dead fish were discovered at the bottom of the pen. The previous manager put this mortality down in week 35 despite the site being fallow. After reviewing the fish numbers, movement records off site and the circumstances surrounding that mortality record, it was decided that the mortality percentage for that week should be calculated against the number of fish transferred off site in the previous days. East Tarbert Bay therefore had a mortality percentage of 0.077% for week 35, 2025.
Morts ensiled and then sold for biofuel. Billy Bowie picks up and takes to Dundas.
Treatments: FW/FLS 25/10/2025 - for sealice. Alphamax/FLS: 07/09/2025 and 27/09/2025 - prescription seen, all cages treated due to sealice.
Health surveillance: Vets 23/09/2025 - Aquatic vets visit 9 days after fish transfer onto site. No issues found, signs of early maturation. Company biology team 15/09/2025 - Low PGD scores, signs of early maturation. Patogen report 10/10/25 - 19/20 positive Aeromonas salmonicida, 12/21 positive piscine orthoreovirus, negative for moritella viscosa, SAV, PDV, Pasteurella skyensis O2, Pasteurella atlantica + skyensis O1, 14/21 positive for PMCV and 7/20 positive for Yersinia.
Sealice: Sealice numbers have been low during period checked except since week 38 2025. Druimyeon Bay treated for sealice week 38 (3.6, mainly caligus) - it is theorised that during crowding the lice shed their eggs which went with the tide down to East Tarbert bay, giving rise to the increase in lice numbers. Normally treatments would be synchronous for both sites however the treatment boat was required elsewhere urgently therefore East Tarbert bay was not treated at the same time.
Treatments at East Tarbert Bay have reduced lice numbers. Last weeks figure is 0.45.
The site is currently being used as a grower site with and no full cycles have been carried out since 2021 due to mass mortality events at the time.
During physical inspection of the site only one dead fish was seen across the whole site. One exothalamic fish was observed in one pen and each of the six stocked pens had between 1-5 fish with dark colouration. In all pens the majority of fish were shoaling deeper in the water column. Of fish observed at the water surface, no lice were seen. One pen was being fed at the time of inspection and fish had a good feed response.
One fish was taken from pen 2 for VMD sampling. This fish appeared healthy internally and externally. The fish had 2 sealice on it at the time of sampling. [Original PDF]

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