Grasholmen

Site 11690 · Alver municipality · Production area 4, Nordhordland til Stadt

Below the lice limit, week 39Operated by Lerøy Vest Sjø AS · group Lerøy Seafood Group

0.24Adult female lice per fishLimit 0.50 · below the limitWeek 39, 2026 · Norwegian Food Safety Authority · updated 01 Oct 2026

0Weeks above the limit in 2026of 37 weeks with a countCalculated by the Salmon Ledger · Norwegian Food Safety Authority · updated 01 Oct 2026

7Lice treatments in 2026Latest: Thermal delousing, week 38, 20262026 · Norwegian Food Safety Authority · updated 01 Oct 2026

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

10Wellboat visits in 2026by 2 different vessels · latest 06 Aug 2026Derived from AIS · Norwegian Coastal Administration (AIS) · updated 01 Oct 2026

1Escapes reported1-10 rainbow trout, December 2025Since 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 16–21 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	0.04	0.5	Below the limit
2	0.09	0.5	Below the limit
3	0.05	0.5	Below the limit
4	0.11	0.5	Below the limit
5	0.09	0.5	Below the limit
6	0.14	0.5	Below the limit
7	0.17	0.5	Below the limit
8	0.16	0.5	Below the limit
9	0.31	0.5	Below the limit
10	0.18	0.5	Below the limit
11	0.28	0.5	Below the limit
12	0.15	0.5	Below the limit
13	0.10	0.5	Below the limit
14	0.03	0.5	Below the limit
15	0.05	0.5	Below the limit
16	0.05	0.2	Below the limit
17	0.04	0.2	Below the limit
18	0.10	0.2	Below the limit
19	0.04	0.2	Below the limit
20	0.05	0.2	Below the limit
21	0.11	0.2	Below the limit
22	0.12	0.5	Below the limit
23	0.35	0.5	Below the limit
24	unknown	0.5	Not reported
25	unknown	0.5	Not reported
26	0.08	0.5	Below the limit
27	0.08	0.5	Below the limit
28	0.10	0.5	Below the limit
29	0.13	0.5	Below the limit
30	0.11	0.5	Below the limit
31	0.49	0.5	Near the limit
32	0.36	0.5	Below the limit
33	0.39	0.5	Below the limit
34	0.13	0.5	Below the limit
35	0.15	0.5	Below the limit
36	0.36	0.5	Below the limit
37	0.26	0.5	Below the limit
38	0.38	0.5	Below the limit
39	0.24	0.5	Below the limit

Earlier years

20250 of 24 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	0.40	0.5	Near the limit
2	0.18	0.5	Below the limit
3	0.17	0.5	Below the limit
4	0.49	0.5	Near the limit
5	0.43	0.5	Near the limit
6	0.33	0.5	Below the limit
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	0.2	Not reported
17	unknown	0.2	Not reported
18	unknown	0.2	Not reported
19	unknown	0.2	Not reported
20	unknown	0.2	Not reported
21	unknown	0.2	Not reported
22	unknown	0.5	Not reported
23	unknown	0.5	Not reported
24	unknown	0.5	Not reported
25	unknown	0.5	Not reported
26	unknown	0.5	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	0.00	0.5	Below the limit
36	0.01	0.5	Below the limit
37	0.01	0.5	Below the limit
38	0.01	0.5	Below the limit
39	0.02	0.5	Below the limit
40	0.04	0.5	Below the limit
41	0.07	0.5	Below the limit
42	0.07	0.5	Below the limit
43	0.09	0.5	Below the limit
44	0.10	0.5	Below the limit
45	0.13	0.5	Below the limit
46	0.14	0.5	Below the limit
47	0.22	0.5	Below the limit
48	0.27	0.5	Below the limit
49	0.28	0.5	Below the limit
50	0.41	0.5	Near the limit
51	0.22	0.5	Below the limit
52	0.04	0.5	Below the limit

20241 of 52 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, 2024
Week	Adult female lice per fish	Lice limit	Status
1	0.06	0.5	Below the limit
2	0.10	0.5	Below the limit
3	0.10	0.5	Below the limit
4	0.11	0.5	Below the limit
5	0.08	0.5	Below the limit
6	0.16	0.5	Below the limit
7	0.24	0.5	Below the limit
8	0.15	0.5	Below the limit
9	0.14	0.5	Below the limit
10	0.43	0.5	Near the limit
11	0.39	0.5	Below the limit
12	0.20	0.5	Below the limit
13	0.08	0.5	Below the limit
14	0.14	0.5	Below the limit
15	0.08	0.5	Below the limit
16	0.08	0.2	Below the limit
17	0.08	0.2	Below the limit
18	0.09	0.2	Below the limit
19	0.08	0.2	Below the limit
20	0.10	0.2	Below the limit
21	0.08	0.2	Below the limit
22	0.10	0.5	Below the limit
23	0.10	0.5	Below the limit
24	0.06	0.5	Below the limit
25	0.06	0.5	Below the limit
26	0.11	0.5	Below the limit
27	0.11	0.5	Below the limit
28	0.11	0.5	Below the limit
29	0.20	0.5	Below the limit
30	0.26	0.5	Below the limit
31	0.24	0.5	Below the limit
32	0.46	0.5	Near the limit
33	0.18	0.5	Below the limit
34	0.15	0.5	Below the limit
35	0.23	0.5	Below the limit
36	0.23	0.5	Below the limit
37	0.84	0.5	Above the limit
38	0.25	0.5	Below the limit
39	0.05	0.5	Below the limit
40	0.15	0.5	Below the limit
41	0.10	0.5	Below the limit
42	0.37	0.5	Below the limit
43	0.16	0.5	Below the limit
44	0.10	0.5	Below the limit
45	0.13	0.5	Below the limit
46	0.25	0.5	Below the limit
47	0.11	0.5	Below the limit
48	0.11	0.5	Below the limit
49	0.10	0.5	Below the limit
50	0.34	0.5	Below the limit
51	0.13	0.5	Below the limit
52	0.15	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	unknown	0.5	Not reported
41	unknown	0.5	Not reported
42	unknown	0.5	Not reported
43	unknown	0.5	Not reported
44	unknown	0.5	Not reported
45	0.00	0.5	Below the limit
46	0.00	0.5	Below the limit
47	0.00	0.5	Below the limit
48	0.00	0.5	Below the limit
49	0.00	0.5	Below the limit
50	0.00	0.5	Below the limit
51	0.01	0.5	Below the limit
52	0.04	0.5	Below the limit

Treatments

Norwegian Food Safety Authority

Week 38, 2026
Thermal delousing2 pens
Week 35, 2026
Thermal delousing, Mechanical delousing2 pens
Week 32, 2026
Thermal delousing4 pens
Week 19, 2026
Thermal delousing3 pens

Show all 18

Week 12, 2026
Thermal delousing, Freshwater treatment5 pens
Week 52, 2025
Medicinal bath2 pens · Azamethiphos
Week 51, 2025
Medicinal bath2 pens · Azamethiphos
Week 5, 2025
Thermal delousing2 pens
Week 51, 2024
Thermal delousing4 pens
Week 47, 2024
Thermal delousing2 pens
Week 46, 2024
Thermal delousing2 pens
Week 43, 2024
Thermal delousing4 pens
Week 39, 2024
Thermal delousingWhole site
Week 38, 2024
Thermal delousing2 pens
Week 37, 2024
Thermal delousing2 pens
Week 33, 2024
Thermal delousingWhole site
Week 12, 2024
Medicinal bathWhole site · Azamethiphos
Week 2, 2024
Medicinal feedWhole site · Emamectin benzoat

Disease

Norwegian Food Safety Authority

No cases in the Food Safety Authority's register of notifiable diseases (since 26 Nov 2024).

Escapes

Directorate of Fisheries

21 Dec 2025
1-10 rainbow trout escapedCause: Uavklart · recaptured 1 · Directorate of Fisheries

Wellboat visits

10 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
06 Aug 2026	Seigrunn	Stolane	5 h 22 min
05 Aug 2026	Seigrunn	Stolane	21 h 6 min
04 Aug 2026	Seigrunn	Stolane	12 h 0 min
10 Jun 2026	Seihav	Storevikholmen	41 h 23 min
09 Jun 2026	Seihav	Storevikholmen	16 h 46 min
08 Jun 2026	Seihav	Storevikholmen	4 h 12 min
04 May 2026	Seihav	Stolane	33 h 25 min
21 Mar 2026	Seihav	Ramsvik	18 h 12 min
20 Mar 2026	Seihav	Ramsvik	5 h 26 min
20 Mar 2026	Seihav	Ramsvik	7 h 55 min
22 Dec 2025	Seihav	Ramsvik	18 h 55 min
22 Dec 2025	Seihav	Ramsvik	6 h 31 min

Show 10 older visits

Arrival	Vessel	Previous farm (14 days)	Duration
21 Dec 2025	Seihav	Ramsvik	8 h 2 min
21 Dec 2025	Seihav	Ramsvik	8 h 42 min
05 Oct 2025	Mowi Star	Djupeleget	7 h 32 min
04 Oct 2025	Mowi Star	Djupeleget	1 h 48 min
01 Oct 2025	Mowi Star	Syrtangen	1 h 8 min
20 Mar 2024	Seihav	Storoksen	2 h 47 min
20 Mar 2024	Seihav	Storoksen	4 h 33 min
20 Mar 2024	Seihav	Storoksen	5 h 3 min
19 Mar 2024	Seihav	Storoksen	1 h 15 min
19 Mar 2024	Seihav	Storoksen	4 h 15 min

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

Licences

Site MAB: 3,120 tonnes

Licence	Type	Capacity	Holder
H OR 0004	Kommersiell / matfiskSalmon, Rainbow trout, Trout	648 t	Lerøy Vest Sjø AS
H OR 0026	Kommersiell / matfiskSalmon, Rainbow trout, Trout	648 t	Lerøy Vest Sjø AS
H R 0006	Kommersiell / matfiskSalmon, Rainbow trout, Trout	1,080 t	Lerøy Vest Sjø AS
H R 0009	Kommersiell / matfiskSalmon, Rainbow trout, Trout	648 t	Lerøy Vest Sjø AS
H R 0016	Kommersiell / matfiskSalmon, Rainbow trout, Trout	648 t	Lerøy Vest Sjø AS

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