IMR_Postsmolt_2025_Sogn

Havforskningsinstituttet Tråling Postsmolt laks 2025 Sognefjord

Dataset Creator	Dataset Title	Dataset Release Date	Dataset Publisher	Dataset DOI	Online Resource
Rosa Maria Serra Llinares, Rune Nilsen, Pål Næverlid Sævik, Alison Harvey, Vidar Wennevik og Ørjan Karlsen	Havforskningsinstituttet Tråling Postsmolt laks 2025 Sognefjord	2025-08-27T00:00:00:00Z	Institute of Marine Research	10.21335/NMDC-1160298977	http://metadata.nmdc.no/metadata-api/landingpage/173de2a1d9e3c51643a89e85c6edf116

Role	First Name	Last Name	Email	Middle Name
DIF Author	Arnfinn	Morvik	arnfinn.morvik@hi.no
Technical Contact	Ørjan	Karlsen
Technical Contact	Vidar	Wennevik
Technical Contact	Rune	Nilsen
Technical Contact	Alison	Harvey
Investigator	Rosa	Llinares		Maria Serra
Technical Contact	Pål	Sævik		Næverlid

Category	Topic	Term	Variable Level 1	Variable Level 2	Variable Level 3
EARTH SCIENCE	BIOLOGICAL CLASSIFICATION	ANIMALS/VERTEBRATES	FISH	RAY-FINNED FISHES	SALMONS/TROUTS

Oceans

Salmon Lice

Start Date	Stop Date
2025-05-10	2025-06-03

Complete

Location Category	Location Type	Location Subregion1	Location Subregion2
Ocean	Atlantic Ocean	North Atlantic Ocean	Norwegian Sea

unrestricted

Institute of Marine Research

Data Center Name	Personnel	Data Center URL
Institute of Marine Research, Norwegian Marine Data Center Institute of Marine Research, Norwegian Marine Data Center	Datacenter Arnfinn Morvik arnfinn.morvik@hi.no
NO/IMR Institute of Marine Research	Originating institution Rune Nilsen	http://www.imr.no

Distribution Media	Distribution Format
FTP	Microsoft Excel

The dataset includes Institute of Marine Research data from trawl stations in Sognefjord, Norway in 2025. Post-smolts were collected in the outer parts of the fjord systems in late spring and early summer with a specialized surface trawl for live fish sampling, towed behind a suitable fishing vessel (15-25 m). The trawl is 5 m deep and up to 35 m wide depending on speed through water. The trawl is mounted to a system where smaller catch, such as post-smolts are separated from other catch, and remain free swimming in low turbulence in a hydrodynamic aquarium. The separation takes place when the current flow through a net tunnel and over two 45 degrees racks. The first rack (10 mm between bars) lifts the catch to the next (20 mm between bars) where the separation is done. Everything wider than 20 mm will continue to the cod end of the trawl. Details of the post-smolt trawl are described in Holst and McDonald (2000), Fisheries Research 48, pp 87-91. The standard trawling speed is 2–3 knots (STW), with an average duration of approximately 45 minutes per haul. Lice counts on post-smolts were performed on the ship as soon as possible after they were captured. The fish were killed using an overdose of Benzocaine 200 mg/ml. Lice counts were performed with the fish submerged in a white plastic tub (5-10 l) using a strong headlamp (>500 lumen). The counts were only performed by personnel with special training in identification of all salmon lice stages. The following categories were recorded: copepodite, chalimus 1, chalimus 2, pre-adult, adult male and adult female. Fish length in mm and mass in gram were recorded. All post-smolts were then frozen for subsequent analysis.

URL Content Type	URL
GET DATA	https://ftp.nmdc.no/nmdc/IMR/lakselus/Havforskningsinstituttet_Traaling_Postsmolt_laks_2025_Sognefjord.xlsx

Norwegian Marine Datacentre

CEOS IDN DIF

9.7.1

2025-08-27T00:00:00:00Z

CC BY 4.0

POLYGON((5.2998 60.934599999999996,5.0485 60.934599999999996,5.0485 61.249900000000004,5.2998 61.249900000000004,5.2998 60.934599999999996))