Site Details: Creag an T'Sagairt (Loch Hourn)

Arnisdale
Glenelg
Ross-shire
IV40 8JH
Operator: Mowi Scotland Ltd
Water type: Seawater

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Average female lice per fish

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Salmon Scotland mortality

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Cumulative mortality over full production cycle

Loch Hourn Production cycle end date: Feb 2018
Total losses: 16.4 %

Loch Hourn Production cycle end date: Jan 2020
Total losses: 11.4 %

Loch Hourn Production cycle end date: Dec 2021
Total losses: 8.3 %

Loch Hourn Production cycle end date: Oct 2023
Total losses: 34.6 %

Loch Hourn Production cycle end date: Mar 2024
Total losses: 3.2 %

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Fish Health Inspectorate mortality

Date:
15/05/23-21/05/23
Mortality:
31,099
Mortality Rate:
3.01%
Reason given: Thermolicer Treatment
Thermolicer Treatment
Called for further information - handling during thermolicer treatment caused mortalities in population that has CMS, treatment was aborted. Treatment has now been conducted with FW and improvements seen. FHI to monitor.
Date:
22/05/23-28/05/23
Mortality:
10,093
Mortality Rate:
1.01%
Reason given: Thermolicer Treatment
Thermolicer Treatment
Alternative treatment conducted
Health director called for more information. Occurred during crowding of fish before thermolicer treatment. The treatment was aborted and a new method of treatment was organised using the FLS system. This new system uses a combination of two physical treatments to first weaken the lice and them removed them with water. This method of treatment is reportedly more gentle on the fish. This reduced mortality and removed lice. FHI to monitor
Date:
19/06/23-25/06/23
Mortality:
14,082
Mortality Rate:
1.45%
Reason given: Gill Issues - jellyfish
Gill Issues - jellyfish
Business contacted: This year seems to be mostly Obelia (jellyfish), which is different from previous years. Have also started to see increased level of concussion on site through a sudden influx of adult Caligus, which are susppected to have come in with wild fish as previously no juvenile stages of Caligus have been observed on site.
Business contacted for additional information. FHI to monitor.
Date:
26/06/23-02/07/23
Mortality:
18,416
Mortality Rate:
2.78%
Reason given: Gill issues - jellyfish
Gill issues - jellyfish
Unable to get in touch with site contact. FHI to monitor.
Date:
03/07/23-09/07/23
Mortality:
24,436
Mortality Rate:
2.87%
Reason given: Gill issues - jellyfish
Gill issues - jellyfish
Date:
10/07/23-16/07/23
Mortality:
49,907
Mortality Rate:
6.16%
Reason given: Gill infections / CMS
Gill infections / CMS
Site is positive for HSMI and CMS. Site is also positive for AGD and PGD, with also jellyfish damage being observed. Handling of fish has exacerbated mortality. Due to sealice increasing on site, intervention via FW and FLS conducted in WK 28. Targeted harvestes scheduled for WK30. In addition, weekly health visits with diagnostic sampling has been occurring.
Business correspondent contacted for further information. FHI to monitor.
Date:
24/07/23-30/07/23
Mortality:
11,486
Mortality Rate:
1.52%
Reason given: Gill infections / HSMI
Gill infections / HSMI
business contacted: FW treatment, HSMI
FHI to monitor.
Date:
31/07/23-06/08/23
Mortality:
13,927
Mortality Rate:
1.87%
Reason given: Gill infections / CMS
Gill infections / CMS
FHI to monitor
Date:
07/08/23-13/08/23
Mortality:
17,859
Mortality Rate:
2.44%
Reason given: Gill infections / CMS
Gill infections / CMS
Site contacted for further information, Main cause of mortality is currently from CMS and gill infections. Signs of bacterial infections have been identified in some of the stocks (frunculosis). The site is sheduled to begin harvesting from Week 34, harvesting to fallow by week 38.
FHI to monitor.
Date:
14/08/23-20/08/23
Mortality:
22,458
Mortality Rate:
3.15%
Reason given: Gill infections / CMS
Gill infections / CMS
Main cause of mortality is currently from CMS and gill infections. Signs of bacterial infections have been identified in some of the stocks (frunculosis). The site is sheduled to begin harvesting from Week 34, harvesting to fallow by week 38.
FHI to monitor.
Date:
21/08/23-27/08/23
Mortality:
19,089
Mortality Rate:
2.76%
Reason given: Gill infections / CMS
Gill infections / CMS
Targeted harvesting ongoing, issue with early maturation and gill health from jellyfish, mortlities will continue but will imporve as biomass is reduced,
FHI to monitor.
Date:
28/08/23-03/09/23
Mortality:
11,794
Mortality Rate:
2.02%
Reason given: Gill infections / CMS
Gill infections / CMS
Ongoing mortality issue. FHI visit scheduled
Date:
04/09/23-10/09/23
Mortality:
5,796
Mortality Rate:
1.28%
Reason given: Gill infections / CMS
Gill infections / CMS
Update 18/09/2023: Harvesting to fallow in next 3-4 weeks. Early maturation of fish. Reducing handling.
Site inspected 07/09/2023. FHI to monitor.
Date:
11/09/23-17/09/23
Mortality:
4,806
Mortality Rate:
1.08%
Reason given: Gill infections/HSMI
Gill infections/HSMI
Harvesting ongoing, numbers have increased mainly due to the increased handling and background gill issues, HSMI and jellyfish part of the cause.
FHI to monitor.
Date:
02/10/23-08/10/23
Mortality:
2,594
Mortality Rate:
1.24%
Reason given: Gills
Gills
Biomass and stocking density has been reduced significantly and mortality trends are stabilising
FHI to monitor.
Date:
09/10/23-15/10/23
Mortality:
1,796
Mortality Rate:
1.03%
Reason given: Gills
Gills
Mortality down. FHI to monitor
Date:
23/10/23-29/10/23
Mortality:
2,700
Mortality Rate:
3.93%
Reason given: Gills
Gills
Site now fallow
No further action, site fallow
Date:
04/12/23-10/12/23
Mortality:
3,486
Mortality Rate:
1.26%
Reason given: Transportation
Transportation
FHI to monitor.
Date:
30/09/24-06/10/24
Mortality:
20,284
Mortality Rate:
1.23%
Reason given: Gill infections
Gill infections
Business contacted (info received 16/10/24): AGD FW treatment 30/9-6/10.
First report this cycle. FHI to monitor.
Date:
28/10/24-03/11/24
Mortality:
18,705
Mortality Rate:
1.29%
Reason given: Gill infections
Gill infections
Business contacted for additional information.
Business contacted for additional information. FHI to monitor.
Date:
16/12/24-22/12/24
Mortality:
20,050
Mortality Rate:
1.97%
Reason given: Bacterial disease
Bacterial disease
Antibiotic treatment commenced 20th Dec. Business contacted for additional information: Yersinia/ERM identified and treated with antibiotic. Mortality subsequently reduced.
Business contacted for additional information.

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Inspection reports

Case Number: 2022-0477


Download Additional peaks in salmon mortality in 2021 wk 30 1.32% 3604 (CMS), wk 31 1.61% 4426 (CMS), wk 32 1.90% 4139 (CMS), wk 38 3.80 4649 (transfer losses), wk 40 2.61% 6092 records detail 3538 fw to sw transfer loss, 2122 SW to SW. The FW to
SW entry was confirmed to be an error when inputting data.
Additional peaks in lumpfish mortality 2020 wk 39 8594 9.23% (AGD & other non infectious causes), wk 41 7.78% 3695 AGD, handling and transport losses), wk 43 7.19% 6685 (no specific cause)
No issues reported with the new input, fish are feeding well. [Original PDF]

Case Number: 2023-0427


Download The site was inspected following reports of increased mortality, due to gill health issues. While on site it was noted that mortality levels had decreased and gill health had improved. The stock on site was swimming deep and staff members were checking daily for moribund fish, although very few had been seen. This was reflected during the inspection of the site and one letheragic fish was seen and was unable to be caught for diagnostic sampling.
In response to the mortality issues the site had begun targeted harvesting of the worst affected cages and is expected to be fallow in early October. [Original PDF]

Case Number: 2025-0126


Download Business health report conducted 28/04/2025 - some physical damage was observed following FW/ FLS treatments. Business health report 20/03/2025 - fish sampled for testing following elevated background mortalities. All fish were moribund, tested positive for CGD, HSMI, Tenacibaculum and Yersinia.
Elevated Lumpsucker mortalities - 2022 wk40 22015 (17.52%) wk41 15681 (15.13%) - due runts/ harvesting. wk50 10119
(11.22%), 2023 wk22 7470 (11.71%) wk23 7968 (13.67%) wk25 7551 (17.50%)- due to harvesting. Site cull cleaner fish at harvest.
Site had recently changed barges. During period of the barge being replaced, any mortalities were collected as whole fish into tubs and collected by Bowans (Locheil Logistics).
Stock were observed to be shoaling and feeding well whilst swimming deep in the water column. Fish had a good feed and stimuli response. Few spinal deformities were observed across site. 3 mortalities and 1 moribund were observed across site.
Some fish were observed to have lesions but were healing well, site had attributed this to recent FLS/ FW treatments.
Compared to the other pens, stock in pen 2 were observed to have an increase of number fish hanging around the sides of the pen and appeared slightly lethargic but had good body condition. Pen 2 had only recently finished a FW/FLS treatment and the site had also suggested to changes with the feed barge system is causing less feed being put out which may be attributing for pen 2 being slightly lethargic.
2 fish were collected for VMD. The fish were observed to be in good condition externally and internally.
Site records and stock were inspected by whilst supervised by . VMD was sampled by whilst supervised by
. [Original PDF]

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