Average female lice per fish

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Salmon Scotland mortality

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Cumulative mortality over full production cycle

Production cycle end date: Jul 2019
Total losses: 29.5 %

Production cycle end date: Jul 2021
Total losses: 10 %

Production cycle end date: Sep 2023
Total losses: 57.6 %

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Inspection reports

Case Number: 2020-0079

Download Mortalities have been very low throughout cycle since stocking. Monitored daily by camera. First fish likely to be harvested in the next few months.
Sea lice counts very low. Sea lice skirts were in place prior to stocking and just recently removed. Two slice treatments administered one in April and one in July - July treatment due to slight rise in Caligus numbers observed. No other treatments conducted, company generally favour freshwater for sea lice treatments, however other methods are available - chemotherapeutants and optilicer. Details of decision making process for choosing intervention not written into sea lice management plan - to look further into this.
Top nets and predator nets in place - no issues with predation except some bird pecking earlier in cycle which was prevented by tightening sagging top nets.
All records except movement records inspected by remotely.
Site Inspection and sampling by
Stock on site appeared in good condition, site manager reported that gill health had been good this year and lice numbers are low. Fish sampled for VMD appeared healthy. During FW treatments, the site have been splitting the fish over two wells to reduce stocking density during treatment. Site reported very low mortalities attributed to treatments.
Restructuring within the MA with three new site managers (one looks after Score Holms and West of Burwick, one looks after
Langa Isle (East) and North Papa and the third looks after Setter Voe, which is operating out of old Skretting shed in
Scalloway.
FW treatment due to be conducted beginning of week 39. [Original PDF]

Case Number: 2022-0529

Download Site inspection and paper work conducted by , observed by .
Site inspected in rough weather, visibility was poor and fish were residing deep within the pen. No moribund or lethargic fish observed during the physical inspection of the site.
Routine sea lice counts were being conducted during the time of visit, externally no clinical signs of disease was observed.
Moderate to severe gill damage was observed in most fish checked during the lice counts with most fish checked scoring high for PGD. There was a bloom of muggiaea atlantica (micro jellyfish) confirmed at the site in early October which has compromised gill health along with a touch of seasonal AGD. Staff have been monitoring the site daily for plankton levels and has confirmed that jellyfish counts in recent weeks have decreased. With the water temperature on site decreasing the site is hopeful to see an improvement in gill health in the coming weeks. Mortality has remained low and below reporting threshold for this production cycle.
The site treated with FW in week 42, Pen 3 suffered a treatment loss of 5,904 fish resulting from a handling error. Site still below reporting threshold for the week despite this loss.
Fish sampled for VMD appeared healthy from internal examination with the execption of the gills. [Original PDF]

Case Number: 2022-0585

Download Last site inspection conducted on 26/10/2022.
Additional inspection carried out due to high mortalities reported to the FHI in weeks 48 and 49 2022 attributed to CGD, AGD, and treatment loss. This had to be done remotely because of weather issues and airport strikes.
Week 48 - 6.8% 55,944 fish
Week 49 - 7.7% 58,269 fish
A bloom of Muggiaea atlantica (micro jellyfish) compromised gill health in early October, along with seasonal AGD. Mortalities began to increase in week 47 and a wellboat freshwater treatment was carried out on 6/12 as mitigation. This however, resulted in higher mortality numbers. The site switched to hydrogen peroxyde treatments in the following days (12, 13, 16, 18,
19/12), which have been more successful. All affected cages have now been treated, and will be retreated in the coming weeks.
Only one cage on site is not being treated as it's not displaying gill issues/mortalities. The fish are Aquagen stock rather than
Stofnfiskur.
Company veterinarian currently out on site. [Original PDF]

Case Number: 2023-0009

Download Following consecutive reports of mortality, a site visit was planned for the 24/01/2023. Weather did not permit the inspection of the site on the 24/01 and was rescheduled for the 25/01. Paperwork was inspected on 25/01/2023.
A bloom of Muggiaea atlantica (micro jellyfish) compromised gill health in early October, along with seasonal AGD and most recently diagnosed with CMS. PGD however is the main cause of mortality (24/01/2023). Following a passive surveillance inspection on the 20/12/2022, mortalities continued to be above the reporting threshold. The site conducted its last hydrogen peroxide treatment on 19/12/2022, which was found to be successful. No further chemical treatments have been conducted on site since 19/12/2022. FW is planned to be the next treatment and if weather permits begins w/b 30/01/2023. The FW treatments will target pens believed to cope with handling and attempts will lastly be made in pens 1, 2, 10, 11 (worst affected).
Harvest of worst affected pens is an option. Due to weather and prioritising mortality removal from site, fish health visits have been limited since 20/12/2022, however next scheduled visit along with routine histology, bacteriology and PCR is planned for the 26/01/2023.
The stock origins are from Girlsta Hatchery and Barcaldine Smolt Unit; with primary input of fish from Langa Isle (East) in
September and one pen stocked with transferred fish from Holms Geo in November, respectively.
Mortality (recent weeks):
20/12/2022-26/12/2022: 1.17%, 8074
27/12/2022-02/01/2022: 1.97%, 13470
03/01/2023-09/01/2023: 6.37%, 42780; pen 10, 4, 2, 1 most affected
10/01/2023-16/01/2023: 4.59%, 28820; pen 11, 10, 1 and 4 most affected
17/01/2023-23/01/2023: 2.82%, 16430; pen 10, 1, 5 most affected
White circular lesions were observed on the fish as well as some 'boils'/raised scales on a few fish both observed on site and during sampling. Bacteriology plates of the lesions were taken on F2, F3 and F4.
Last lice count was conducted on 29/12/2022. Weather and mortality removal have not permitted lice counts on site. Last lice counts were conducted using Optimease (only 7 day withdrawal compared to TMS). Fish are currently off feed.
FW treatment boat is planned to arrive on 30/01/2023 and plan is to prioritise to treat those with least mortality.
No cleanerfish held on site. [Original PDF]

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