Ulværholmen

Site 13570 · Hitra municipality · Production area 6, Nordmøre og Sør-Trøndelag

Status unknown: not reported in week 39Operated by Lerøy Midt Sjø AS · group Lerøy Seafood Group

unknownAdult female lice per fishNo count in week 39. Latest: 1.56 in week 44, 2025Week 39, 2026 · Norwegian Food Safety Authority · updated 01 Oct 2026

unknownWeeks above the limit in 2026No weeks with a count in 2026Calculated by the Salmon Ledger · Norwegian Food Safety Authority · updated 01 Oct 2026

unknownLice treatments in 2026No lice reports in 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

0Wellboat visits in 2026Latest visit 12 Nov 2025Derived from AIS · Norwegian Coastal Administration (AIS) · updated 01 Oct 2026

0Escapes reportedNone reportedSince 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.

2025

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

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Adult female lice per fish per week, 2025
Week	Adult female lice per fish	Lice limit	Status
1	0.00	0.5	Below the limit
2	0.00	0.5	Below the limit
3	0.00	0.5	Below the limit
4	0.00	0.5	Below the limit
5	0.00	0.5	Below the limit
6	0.00	0.5	Below the limit
7	0.01	0.5	Below the limit
8	0.00	0.5	Below the limit
9	0.01	0.5	Below the limit
10	0.01	0.5	Below the limit
11	0.02	0.5	Below the limit
12	0.02	0.5	Below the limit
13	0.02	0.5	Below the limit
14	0.02	0.5	Below the limit
15	0.03	0.5	Below the limit
16	0.03	0.2	Below the limit
17	0.03	0.2	Below the limit
18	0.03	0.2	Below the limit
19	0.04	0.2	Below the limit
20	0.04	0.2	Below the limit
21	0.05	0.2	Below the limit
22	0.06	0.5	Below the limit
23	0.08	0.5	Below the limit
24	0.08	0.5	Below the limit
25	0.09	0.5	Below the limit
26	0.11	0.5	Below the limit
27	0.17	0.5	Below the limit
28	0.24	0.5	Below the limit
29	0.42	0.5	Near the limit
30	0.58	0.5	Above the limit
31	0.58	0.5	Above the limit
32	0.75	0.5	Above the limit
33	0.24	0.5	Below the limit
34	0.14	0.5	Below the limit
35	0.82	0.5	Above the limit
36	1.86	0.5	Above the limit
37	0.47	0.5	Near the limit
38	0.26	0.5	Below the limit
39	0.22	0.5	Below the limit
40	0.90	0.5	Above the limit
41	3.98	0.5	Above the limit
42	3.04	0.5	Above the limit
43	1.53	0.5	Above the limit
44	1.56	0.5	Above the limit
45	unknown	0.5	Not reported
46	unknown	0.5	Not reported
47	unknown	0.5	Not reported
48	unknown	0.5	Not reported
49	unknown	0.5	Not reported
50	unknown	0.5	Not reported
51	unknown	0.5	Not reported
52	unknown	0.5	Not reported

Earlier years

20240 of 5 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

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Adult female lice per fish per week, 2024
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	0.2	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	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
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	unknown	0.5	Not reported
46	unknown	0.5	Not reported
47	unknown	0.5	Not reported
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	0.00	0.5	Below the limit
52	0.00	0.5	Below the limit

20230 of 4 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

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Adult female lice per fish per week, 2023
Week	Adult female lice per fish	Lice limit	Status
40	0.25	0.5	Below the limit
41	0.23	0.5	Below the limit
42	0.09	0.5	Below the limit
43	0.40	0.5	Near the limit
44	unknown	0.5	Not reported
45	unknown	0.5	Not reported
46	unknown	0.5	Not reported
47	unknown	0.5	Not reported
48	unknown	0.5	Not reported
49	unknown	0.5	Not reported
50	unknown	0.5	Not reported
51	unknown	0.5	Not reported
52	unknown	0.5	Not reported

Treatments

Norwegian Food Safety Authority

Week 44, 2025
Freshwater treatment, Mechanical delousing4 pens
Week 43, 2025
Thermal delousing, Freshwater treatment, Mechanical delousing3 pens
Week 42, 2025
Mechanical delousingWhole site
Week 38, 2025
Mechanical delousing3 pens

Show all 9

Week 37, 2025
Mechanical delousing, Freshwater treatment8 pens
Week 36, 2025
Freshwater treatment, Mechanical delousing4 pens
Week 33, 2025
Medicinal bath5 pens · Azamethiphos
Week 31, 2025
Mechanical delousing, Freshwater treatment4 pens
Week 40, 2023
Medicinal bath1 pen · Andrelegemidler

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

No escapes reported from this site since 2006.

Wellboat visits

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
12 Nov 2025	Froey Viking	Ringholmen	4 h 32 min
10 Nov 2025	Froey Viking	Ringholmen	2 h 32 min
27 Oct 2025	Froy Hovding	Langskjæra	35 h 37 min
26 Oct 2025	Froy Hovding	Langskjæra	14 h 38 min
16 Sep 2025	Froy Hovding	Hausan	8 h 21 min
09 Sep 2025	Froy Hovding	Slåttholmen	21 h 50 min
07 Sep 2025	Froy Hovding	Slåttholmen	31 h 16 min
06 Sep 2025	Froy Hovding	Slåttholmen	33 h 21 min
15 Aug 2025	Froy Hovding	Reitholmen	4 h 15 min
14 Aug 2025	Froy Hovding	Reitholmen	9 h 9 min
13 Aug 2025	Froy Hovding	Reitholmen	17 h 18 min
12 Aug 2025	Froy Hovding	Reitholmen	12 h 41 min

Show 9 older visits

Arrival	Vessel	Previous farm (14 days)	Duration
11 Aug 2025	Froy Hovding	Reitholmen	13 h 47 min
10 Aug 2025	Froy Hovding	Reitholmen	5 h 22 min
03 Aug 2025	Froy Hovding	Reitholmen	1 h 2 min
02 Aug 2025	Froy Hovding	Reitholmen	30 h 52 min
01 Aug 2025	Froy Hovding	Reitholmen	2 h 52 min
26 Jul 2025	Tonny	Fætten	56 min
06 Dec 2024	Froey Viking	Aursøysva disease or zone there	2 h 32 min
30 Nov 2024	Froey Viking	Aursøysva disease or zone there	9 h 27 min
29 Nov 2024	Froey Viking	Aursøysva disease or zone there	6 h 31 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
ST H 0019	Kommersiell / matfiskSalmon, Rainbow trout, Trout	822 t	Lerøy Midt Sjø AS
ST H 0022	Kommersiell / matfiskSalmon, Rainbow trout, Trout	820 t	Lerøy Midt Sjø AS
ST HE 0001	Kommersiell / matfiskSalmon, Rainbow trout, Trout	805 t	Lerøy Midt Sjø AS
ST HE 0011	Kommersiell / matfiskSalmon, Rainbow trout, Trout	805 t	Lerøy Midt Sjø AS

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