Site Details: Grey Horse Channel

Hoebeg Cheesebay
Loch Maddy
North Uist
HS6 5AT
Operator: Mowi Scotland Ltd
Water type: Seawater

Average female lice per fish

Source

Salmon Scotland mortality

Source

Cumulative mortality over full production cycle

Grey Horse Channel Production cycle end date: Feb 2019
Total losses: 28.2 %

Grey Horse Channel Production cycle end date: May 2020
Total losses: 17.1 %

Grey Horse Channel Production cycle end date: Dec 2020
Total losses: 8.9 %

Grey Horse Channel Production cycle end date: Jul 2022
Total losses: 44.2 %

Source

Fish Health Inspectorate mortality

Date:
07/02/22-13/02/22
Mortality:
7,688
Mortality Rate:
1.00%
Reason given: Complex gill diseases / Pasteurella Skyensis infection / Treatment losses
Complex gill diseases / Pasteurella Skyensis infection / Treatment losses
Mortalities have reduced from previous weeks. FHI to monitor.
Date:
07/03/22-13/03/22
Mortality:
6,426
Mortality Rate:
1.04%
Reason given: AGD
AGD
Data collected during inspection. Site visited 25/05/2022. Report for 2022-0163 to remind business of agreement in relation to mortality reporting as detailed in A Code of Good Practice for Scottish Finfish Aquaculture.
Date:
28/03/22-03/04/22
Mortality:
5,728
Mortality Rate:
1.02%
Reason given: Seal damage
Seal damage
Data collected during inspection. Site visited 25/05/2022. Report for 2022-0163 to remind business of agreement in relation to mortality reporting as detailed in A Code of Good Practice for Scottish Finfish Aquaculture.
Date:
04/04/22-10/04/22
Mortality:
5,514
Mortality Rate:
1.02%
Reason given: Gill Infection & Predation
Gill Infection & Predation
A number of seal attacks occurred wk 14 which accounts for most of the mortalities with a small part of the percentage down to gill issues. FW treatment scheduled for wk 17. Mortality numbers have reduced wk 15. FHI to monitor
FHI to increase monitoring
Date:
11/04/22-17/04/22
Mortality:
10,209
Mortality Rate:
1.91%
Reason given: Predation / Physical Damage/ Treatment Loss
Predation / Physical Damage/ Treatment Loss
Business correspondent contacted. Predator/seal attacks had already been previously reported. Wk15 has seen an increase in mortalities. The majority of the mortality has been attributed to predation. The other causes are acute loss of thermolicer treatment and presence of AGD. Site is in the process of changing nets to HDPE nets to try and reduce seal damage. FHI to consider inspection. FHI to monitor.
Date:
18/04/22-24/04/22
Mortality:
6,813
Mortality Rate:
1.32%
Reason given: Predation
Predation
On-going third consecutive week above the reporting threshold. Additional information collected last week see MRT02925. Inspector due to visit w/b 23 May. FHI to monitor.
Date:
25/04/22-01/05/22
Mortality:
6,213
Mortality Rate:
1.26%
Reason given: Predation/Gill Disease
Predation/Gill Disease
The majority of the mortality has been attributed to predation and presence of AGD. Site is in the process of changing nets to HDPE nets to try and reduce seal damage. FHI to visit wb 23/05/2022.
Date:
30/05/22-05/06/22
Mortality:
7,457
Mortality Rate:
1.84%
Reason given: Predation
Predation
Site inspected 25/05/22. Site expected to be fallow Aug. 2022.
Date:
06/06/22-12/06/22
Mortality:
4,773
Mortality Rate:
1.22%
Reason given: Gill Infections/seal predation
Gill Infections/seal predation
Site inspected 25/05/22. Site expected to be fallow Aug. 2022.
Date:
13/06/22-19/06/22
Mortality:
5,227
Mortality Rate:
1.36%
Reason given: Gill infections / Seal predation
Gill infections / Seal predation
AGD confirmed on site, freshwater treatments currently in progress. Seals seem to be targeting fish affected by gill issues. FHI to monitor.
Date:
20/06/22-26/06/22
Mortality:
5,618
Mortality Rate:
1.48%
Reason given: Gill Health
Gill Health
On-going mortality. Site inspected 25/05/2022. AGD confirmed on site. Seals seem to be targeting fish affected by gill issues. FHI to monitor.
Date:
27/06/22-03/07/22
Mortality:
7,432
Mortality Rate:
1.99%
Reason given: CMS
CMS
Harvesting
Business correspondent contacted for further info. Increase in mortalities in 2 cages diagnosed with CMS - the harvest plan has been modified to target these cages first. FHI to monitor.
Date:
04/07/22-10/07/22
Mortality:
8,966
Mortality Rate:
2.6%
Reason given: CMS/ Gill Infections
CMS/ Gill Infections
Site being harvested out.
Business correspondent contacted. Site is being harvested out over the next 3 weeks and plans to be fallow by first week of August. CMS and AGD have been confirmed on site. FHI to monitor.
Date:
11/07/22-17/07/22
Mortality:
4,571
Mortality Rate:
2.03%
Reason given: Gill infections
Gill infections
Site due to be harvested out w/e 24th July
Whole site is being harvested out with a planned final harvest date of 24th July. NFA.
Date:
05/09/22-11/09/22
Mortality:
1,396
Mortality Rate:
1.55%
Reason given: Gill-Health Related
Gill-Health Related
Mortality now reduced below reporting threshold
Date:
19/09/22-25/09/22
Mortality:
2,677
Mortality Rate:
1.16%
Reason given: Gill infections / Jellyfish
Gill infections / Jellyfish
Mortality increasing again on last reported week although looks to be dropping in upcoming week. FHI to monitor.
Date:
30/01/23-05/02/23
Mortality:
862
Mortality Rate:
1.26%
Reason given: Predator - seal
Predator - seal
Site to fallow 09/02/23. FHI to monitor.
Date:
28/08/23-03/09/23
Mortality:
14,017
Mortality Rate:
1.23%
Reason given: AGD
AGD
First report this cycle. FHI to monitor.
Date:
04/09/23-10/09/23
Mortality:
24,989
Mortality Rate:
2.21%
Reason given: AGD
AGD
Second report this cycle. Mortalities increased from previous wk. Update 18/09/2023: FW treatment conducted 10/09-22/09/23. Wk 36 mortality reduced to 1.23%.
Business contacted. FHI to monitor.
Date:
11/09/23-17/09/23
Mortality:
18,820
Mortality Rate:
1.70%
Reason given: AGD
AGD
AGD treatments have been ongoing with FW, peroxide had been administered two weeks prior. Morts related to post treatment losses. FHI to monitor.
Date:
25/09/23-01/10/23
Mortality:
12,310
Mortality Rate:
1.14%
Reason given: AGD
AGD
Mortality levels decreased this week. Routine FHI visit scheduled
Date:
02/10/23-08/10/23
Mortality:
47,228
Mortality Rate:
4.43%
Reason given: AGD
AGD
Just finished FW treating
Mortality increased. Routine visit due.
Date:
09/10/23-15/10/23
Mortality:
63,864
Mortality Rate:
6.27%
Reason given: AGD/treatment losses
AGD/treatment losses
FHI visit scheduled
Date:
16/10/23-22/10/23
Mortality:
45,333
Mortality Rate:
4.75%
Reason given: AGD/'Treatment losses
AGD/'Treatment losses
FHI visit scheduled
Date:
23/10/23-29/10/23
Mortality:
26,590
Mortality Rate:
2.93%
Reason given: AGD/treatment losses
AGD/treatment losses
Mortality rate is reducing, site inspection has been scheduled FHI to monitor
Date:
30/10/23-05/11/23
Mortality:
32,807
Mortality Rate:
3.72%
Reason given: AGD/treatment losses
AGD/treatment losses
FW treating currently underway.
FHI visit scheduled.
Date:
06/11/23-12/11/23
Mortality:
29,020
Mortality Rate:
3.91%
Reason given: AGD/treatment loss
AGD/treatment loss
FW treating currently underway.
FHI visited site w/b 13/11. Diagnositc samples taken, awaiting results.
Date:
13/11/23-19/11/23
Mortality:
14,515
Mortality Rate:
2.04%
Reason given: AGD treatment loss/bacterial
AGD treatment loss/bacterial
FHI visited site w/b 13/11. Diagnositc samples taken, awaiting results.
Date:
20/11/23-26/11/23
Mortality:
12,254
Mortality Rate:
1.75%
Reason given: AGD treatment loss/bacterial
AGD treatment loss/bacterial
Site inspected 14/11 (2023-0458). Diagnostic samples taken. AGD, Salmon gill poxvirus and Paranucleospora theridion identified. FHI to monitor.
Date:
27/11/23-03/12/23
Mortality:
9,347
Mortality Rate:
1.36%
Reason given: AGD treatment loss/bacterial
AGD treatment loss/bacterial
Site inspected 14/11 (2023-0458). Diagnostic samples taken. AGD, Salmon gill poxvirus and Paranucleospora theridion identified. FHI to monitor.
Date:
11/12/23-17/12/23
Mortality:
9,031
Mortality Rate:
1.35%
Reason given: AGD
AGD
FHI visited 14/11/23, case number 2023-0458. Diagnostic samples collected. Complex gill disease and SRS.
Date:
18/12/23-24/12/23
Mortality:
6,909
Mortality Rate:
1.04%
Reason given: AGD
AGD
FHI visited 14/11/23, case number 2023-0458. Diagnostic samples taken. Complex gill disease and SRS.
Date:
19/08/24-25/08/24
Mortality:
4,715
Mortality Rate:
1.15%
Reason given: Poor performers / Gill infections
Poor performers / Gill infections
Business contacted (info received 4/9/24): Fish have gill health infections (complex gill disease), they have been treated with freshwater (ending last week), mortality remains low and harvesting in on going weekly.
Business contacted. FHI to monitor.

Source

Inspection reports

Case Number: 2020-0188


Download Mortality information - reported. week 14 - 1.01% - 4566 fish @ 3.3kg- Clinical CMS week 17 - 1.47% - 4757 fish @ 3.4kg - CMS and PD week 18 - 2.04% 5514 fish @ 3.4kg - Losing fish due to CMS and PD, 1 pen had acute losses from treatments. week 19 - 1.89% 4996 fish @ 3.4kg - CMS and PD - Fish being harvested out
Site to be harvested out. Starting 16/05/2020 site expected to be empty by end of may. All pens were first thinned to see if that would help mortality, still seeing consistent CMS and PD mortality so decision to harvest out site was made.
FVG did a full diagnostic which confirmed the presence of CMS and PD. [Original PDF]

Case Number: 2021-0377


Download 5 pens to be transferred to West Loch Tarbert in October due to temperature variations being too high in West Loch Tarbert in the summer while the temperature profile in Cheesebay is colder and more stable.
Lumpfish will be delivered in November to be stocked at 6-10% - from Wales
Salmosan treatment start of September 2021.
Peroxide treatment week 38 2021.
Stock from two different hatcheries. One stock performing worse than the other - not feeding well, lethargic, growing slowly and positive for AGD. Pen 12-13 worst affected, lost 3.5% in week 38.
2 small holes found in pen 12 at 0.5m depth initially thought to be caused by predator damage. Three seals observed on site. incident reported to FHI (Marine Scotland incident reference: MSe061021SAL1) and said to be caused by lumpfish feeder rubbing against already patched net. The holes were repaired upon discovery and the following corrective action will be taken: feeders will be pivoted away from the net to leave a greater distance between them to prevent future holes. In some cases feeders will be removed of cages completely where they are not required. No fish have been lost.
Site currently replacing all top nets.
Physical inspection carried out by and on 06/10/21. VMD sampling done by observed by .
The fish sampled for the VMD showed no clinical signs of disease. [Original PDF]

Case Number: 2022-0163


Download Remote inspection carried out 18/05/2022. Site to be visited following reports of increased mortalities.
A number of seal attacks occurred starting from week 14 2022 which account for most of the mortalities. AGD has also been identified as the additional cause of mortality in the stock transferred from Grey Horse Channel Outer (01/04/2022) This stock has been performing poorly since input, not feeding well and growing slowly. Pens 4, 6, 7, 11, 12, 13, 14.
Harvesting has begun in April and the site is expected to be fallow by August 2022.
Mortality events: weeks 41, 44, 45, 51 & 52 2021 plus weeks 6, 14 - 17 2022 reported to FHI.
Mortalities for weeks 10 & 13 2022 not reported to FHI, see mortality events for additional info.
During the site inspection no moribunds or dead fish could be seen in the cages containing Glenfinnan stock. Some seal damage could be observed in the main population. The pens containing the fish moved from Grey Horse Channel Outer also had a small number of anorexic and lethargic fish near the water surface. Three fish could be sampled and brought to shore for further checks and upon internal examination it was found that they were sexually maturing. No gross pathology was observed. The fish sampled for the VMD looked healthy both internally and externally with minimal sea lice load. [Original PDF]

Case Number: 2023-0458


Download Peaks in salmon mortality 2022, wk 22 7457 (1.84%), wk 23 4,773 (1.22%), wk 24 5,449 (1.41%), wk 25 5,618 (1.48%), wk 26
7,432 (1.99%), wk 27 8,966 (2.60%), wk 28 4571 (2.03%) all AGD and seal predation with some physical damage. Wk 36
1396 (1.55%) all AGD, wk 37 2013 (1.51%), wk 38 2677 (1.16%), fw treatment losses.
Peaks in salmon mortality 2023, wk 35 14017 (1.23%), wk 36 24 989 (2.21%), wk 37 18820 (1.70%), wk 39 15408 (1.39%), wk
40 47228 (4.43%) AGD poor doers.
Salmon mortalities for the last four weeks, wk 44 32,807 (3.72%), wk 43 26590 (2.93%), wk 42 45,333 (4.75%), wk 41 63,864
(6.27%) mainly AGD and treatment losses but also some poor doers.
Peaks in lumpfish mortality 2023, wk 28 12,932 (7.51%), wk 29 28,381 (17.82%) tenacibaculum.
Peaks in wrasse mortality 2023 wk 41 5957 (19.95%) runts and some AGD recorded.
Lumpfish mortality last four weeks, wk45 159 (0.14%), wk 44 166 (0.15%), wk 43 430 (0.39%) wk 42 511 (0.46%).
Wrasse mortality, last four weeks, wk 45 532 (2.27%, wk 44 45 (0.19%), wk 43 214 (0.90%), wk 42 949 (3.86%)
Most recent treatments have included paramove in August and September, freshwater in November, October and September.
Lice numbers are currently low.
Piscirickettsia recently identified, antibiotic treatment is planned.
A number of lethargic and moribund fish observed in all cages.
Some walkways had minor damage following recent storms, these are to be repaired when possible. [Original PDF]

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