Mefaldskjæret

Site 10447 · Alstahaug municipality · Production area 8, Helgeland til Bodø

Status unknown: not reported in week 39Operated by Mowi Seawater Norway AS · group Mowi

unknownAdult female lice per fishNo count in week 39. Latest: 0.39 in week 3, 2026Week 39, 2026 · Norwegian Food Safety Authority · updated 01 Oct 2026

0Weeks above the limit in 2026of 3 weeks with a countCalculated by the Salmon Ledger · Norwegian Food Safety Authority · updated 01 Oct 2026

0Lice treatments in 2026None recorded2026 · Norwegian Food Safety Authority · updated 01 Oct 2026

0Active disease casesNone active · 1 earlierRegister since 26 Nov 2024 · Norwegian Food Safety Authority · updated 01 Oct 2026

14Wellboat visits in 2026by 1 vessel · latest 26 Jan 2026Derived from AIS · Norwegian Coastal Administration (AIS) · updated 01 Oct 2026

4Escapes reported1 salmon, August 2020Since 2006 · Directorate of Fisheries · updated 01 Oct 2026

Sea lice against the limit

Weekly average of adult female lice per fish, as reported by the company. For this site the limit is 0.2 in weeks 21–26 and 0.5 for the rest of the year. Hatched weeks have no count and count neither as above nor below.

2026

Source: Norwegian Food Safety Authority, weekly lice counts reported by the companies · Limit: Regulation on sea lice control § 8 · Updated 01 Oct 2026

Show as table

Adult female lice per fish per week, 2026
Week	Adult female lice per fish	Lice limit	Status
1	0.29	0.5	Below the limit
2	0.35	0.5	Below the limit
3	0.39	0.5	Below the limit
4	unknown	0.5	Reported without a count
5	unknown	0.5	Reported without a count
6	unknown	0.5	Not reported
7	unknown	0.5	Not reported
8	unknown	0.5	Not reported
9	unknown	0.5	Not reported
10	unknown	0.5	Not reported
11	unknown	0.5	Not reported
12	unknown	0.5	Not reported
13	unknown	0.5	Not reported
14	unknown	0.5	Not reported
15	unknown	0.5	Not reported
16	unknown	0.5	Not reported
17	unknown	0.5	Not reported
18	unknown	0.5	Not reported
19	unknown	0.5	Not reported
20	unknown	0.5	Not reported
21	unknown	0.2	Not reported
22	unknown	0.2	Not reported
23	unknown	0.2	Not reported
24	unknown	0.2	Not reported
25	unknown	0.2	Not reported
26	unknown	0.2	Not reported
27	unknown	0.5	Not reported
28	unknown	0.5	Not reported
29	unknown	0.5	Not reported
30	unknown	0.5	Not reported
31	unknown	0.5	Not reported
32	unknown	0.5	Not reported
33	unknown	0.5	Not reported
34	unknown	0.5	Not reported
35	unknown	0.5	Not reported
36	unknown	0.5	Not reported
37	unknown	0.5	Not reported
38	unknown	0.5	Not reported
39	unknown	0.5	Not reported

Earlier years

20250 of 32 weeks with a count above the limit

Source: Norwegian Food Safety Authority, weekly lice counts reported by the companies · Limit: Regulation on sea lice control § 8 · Updated 01 Oct 2026

Show as table

Adult female lice per fish per week, 2025
Week	Adult female lice per fish	Lice limit	Status
1	unknown	0.5	Not reported
2	unknown	0.5	Not reported
3	unknown	0.5	Not reported
4	unknown	0.5	Not reported
5	unknown	0.5	Not reported
6	unknown	0.5	Not reported
7	unknown	0.5	Not reported
8	unknown	0.5	Not reported
9	unknown	0.5	Not reported
10	unknown	0.5	Not reported
11	unknown	0.5	Not reported
12	unknown	0.5	Not reported
13	unknown	0.5	Not reported
14	unknown	0.5	Not reported
15	unknown	0.5	Not reported
16	unknown	0.5	Not reported
17	unknown	0.5	Not reported
18	unknown	0.5	Not reported
19	unknown	0.5	Not reported
20	unknown	0.5	Reported without a count
21	0.00	0.2	Below the limit
22	0.00	0.2	Below the limit
23	0.00	0.2	Below the limit
24	0.00	0.2	Below the limit
25	0.00	0.2	Below the limit
26	0.00	0.2	Below the limit
27	0.00	0.5	Below the limit
28	0.01	0.5	Below the limit
29	0.02	0.5	Below the limit
30	0.02	0.5	Below the limit
31	0.04	0.5	Below the limit
32	0.09	0.5	Below the limit
33	0.15	0.5	Below the limit
34	0.20	0.5	Below the limit
35	0.36	0.5	Below the limit
36	0.06	0.5	Below the limit
37	0.11	0.5	Below the limit
38	0.17	0.5	Below the limit
39	0.46	0.5	Near the limit
40	0.15	0.5	Below the limit
41	0.29	0.5	Below the limit
42	0.23	0.5	Below the limit
43	0.35	0.5	Below the limit
44	0.48	0.5	Near the limit
45	0.14	0.5	Below the limit
46	0.35	0.5	Below the limit
47	0.30	0.5	Below the limit
48	0.36	0.5	Below the limit
49	0.15	0.5	Below the limit
50	0.25	0.5	Below the limit
51	0.25	0.5	Below the limit
52	0.28	0.5	Below the limit

20230 of 8 weeks with a count above the limit (data from week 40)

Source: Norwegian Food Safety Authority, weekly lice counts reported by the companies · Limit: Regulation on sea lice control § 8 · Updated 01 Oct 2026

Show as table

Adult female lice per fish per week, 2023
Week	Adult female lice per fish	Lice limit	Status
40	0.41	0.5	Near the limit
41	0.25	0.5	Below the limit
42	0.22	0.5	Below the limit
43	0.31	0.5	Below the limit
44	0.11	0.5	Below the limit
45	0.16	0.5	Below the limit
46	0.11	0.5	Below the limit
47	0.12	0.5	Below the limit
48	unknown	0.5	Reported without a count
49	unknown	0.5	Reported without a count
50	unknown	0.5	Not reported
51	unknown	0.5	Not reported
52	unknown	0.5	Not reported

Treatments

Norwegian Food Safety Authority

Week 51, 2025
Mechanical delousing1 pen
Week 49, 2025
Thermal delousing2 pens
Week 48, 2025
Thermal delousing2 pens
Week 45, 2025
Thermal delousing4 pens

Show all 13

Week 44, 2025
Mechanical delousing3 pens
Week 43, 2025
Mechanical delousing2 pens
Week 40, 2025
Mechanical delousing6 pens
Week 39, 2025
Mechanical delousing5 pens
Week 36, 2025
Thermal delousing6 pens
Week 35, 2025
Thermal delousing5 pens
Week 44, 2023
Medicinal bath4 pens · Azamethiphos
Week 43, 2023
Medicinal bath3 pens · Azamethiphos
Week 41, 2023
Mechanical delousingWhole site

Disease

Norwegian Food Safety Authority

24 Nov 2024
Pancreas disease (PD): closedSubtype SAV2 · started 16 Nov 2023 · Norwegian Food Safety Authority

Escapes

Directorate of Fisheries

29 Aug 2020
1 salmon escapedCause: Under håving av fisk fra brønnbåt til merd. Hull i bunnen av håven, 1 fisk ramlet ut av håven. Traff kanten av sikkerhetsnett, men sprellet seg ut av nettet og i havet. · recaptured 1 · Directorate of Fisheries
04 Jan 2020
6,500 salmon escapedrecaptured 1 · Directorate of Fisheries
30 Dec 2019
2,540 salmon escapedCause: Det har vært dårlig vær i området i 3 dager. Lift-up er kommet ut av nota - årsak ukjent. Hull av ukjent størrelse på nåværende tidspunkt. Lift-up sikres av teknikere for å begrense omfang. · recaptured 1 · Directorate of Fisheries
15 Aug 2017
1 salmon escapedCause: Håndtering · recaptured 1 · Directorate of Fisheries

Wellboat visits

14 visits in 2026

Visits are derived by us from the Coastal Administration's AIS positions: a fish carrier stationary within 500 metres of the farm for at least 30 minutes. The AIS archive lags about 17 days. A visit is not proof of infection.

Arrival	Vessel	Previous farm (14 days)	Duration
26 Jan 2026	Ronja Havsoy	Hestøy	2 h 5 min
26 Jan 2026	Ronja Havsoy	Hestøy	1 h 53 min
25 Jan 2026	Ronja Havsoy	Hestøy	4 h 10 min
24 Jan 2026	Ronja Havsoy	Hestøy	2 h 8 min
21 Jan 2026	Ronja Havsoy	Hestøy	1 h 59 min
19 Jan 2026	Ronja Havsoy	Hestøy	2 h 0 min
18 Jan 2026	Ronja Havsoy	Hestøy	1 h 24 min
17 Jan 2026	Ronja Havsoy	Hestøy	2 h 13 min
12 Jan 2026	Ronja Havsoy	Hestøy	2 h 30 min
11 Jan 2026	Ronja Havsoy	Hestøy	2 h 36 min
10 Jan 2026	Ronja Havsoy	Hestøy	4 h 36 min
07 Jan 2026	Ronja Havsoy	Hestøy	1 h 44 min

Show 18 older visits

Arrival	Vessel	Previous farm (14 days)	Duration
05 Jan 2026	Ronja Havsoy	Hestøy	2 h 29 min
29 Dec 2025	Ronja Havsoy	Hestøy	2 h 45 min
28 Dec 2025	Ronja Havsoy	Hestøy	3 h 10 min
30 Nov 2025	Ronja Boroy	Hestøy	58 h 8 min
27 Nov 2025	Ronja Boroy	Bjørgan disease or zone there	1 h 41 min
26 Nov 2025	Ro Venture	Nye Skorpa	3 h 51 min
25 Oct 2025	Ronja Havsoy	Hestøy	2 h 36 min
24 Oct 2025	Ronja Havsoy	Hestøy	3 h 47 min
02 Sep 2025	Ronja Boroy	Bjørgan	24 h 45 min
30 Aug 2025	Ronja Boroy	Bjørgan	60 h 30 min
30 Aug 2025	Ronja Boroy	Bjørgan	4 h 52 min
24 May 2025	Ro North	Sæterosen	3 h 27 min
23 May 2025	Ro North	Sæterosen	4 h 3 min
22 May 2025	Ro North	Sæterosen	3 h 41 min
20 May 2025	Ro North	Sæterosen	1 h 15 min
19 May 2025	Ro North	Sæterosen	3 h 43 min
18 May 2025	Ro North	Sæterosen	1 h 20 min
16 May 2025	Ro North	Sæterosen	2 h 57 min

Source: Norwegian Coastal Administration (AIS) · calculated by the Salmon Ledger · updated 01 Oct 2026

Licences

Site MAB: 6,240 tonnes

Licence	Type	Capacity	Holder
N HR 0002	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0003	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0004	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0006	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0010	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0012	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0014	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS
N HR 0016	Kommersiell / matfiskSalmon, Rainbow trout, Trout	804 t	Mowi Seawater Norway AS

Source: Directorate of Fisheries, aquaculture register · updated 01 Oct 2026