Dataset

OTN Loan - Salmonids in Trondheimsfjorden

OTN-OBIS MeasurementOrFact Open in mapper Explore occurrences

This is the OBIS extraction of the Ocean Tracking Network and Norwegian University of Science and Technology (NTNU) OTN Loan - Salmonids in Trondheimsfjorden, consisting of the release tagging metadata, i.e. the location and date when the tagged animal was released, and summarized detection events of tagged individuals. If readers are interested in the source dataset they may also inquire with the project PIs as listed here or on the OTN web site (https://members.oceantrack.org/project?ccode=V2LTROD). Abstract:The aim of the Trondheimfjord project is to get better knowledge of marine migrations of anadrome species (Atlantic salmon, Brown trout) from rivers draining to the Trondheim Fjord. The fjord is a national salmon fjord (a kind of MPA), which means that salmon aquaculture is prohibited. But outside the fjord, one of the most intensive areas for open net pen salmon aquaculture in Norway is located.The two overall hypotheses to test are that a) Atlantic salmon only spent few days in the protected fjord system before heading out to the open sea and b) that brown trout stay within the protected fjord system during the whole marine feeding season. Additionally, we will explore in more details the individual migratory behaviour of the tagged fish and related that to physiological status, previous growth rates, sex and body size. The outcome will be crucial knowledge for regional coastal zone planning and will be of high value as background information when the Norwegian traffic light system, which regulate the aquaculture production, will be evaluated in the years to come.

Citation: Davidsen, J.G., Eldøy, S.H. 2022. Salmonid migrations in Trondheimsfjorden. Accessed via the Ocean Tracking Network OBIS IPT on INSERT DATE

Published: November 05, 2025 at 20:57

License: This work is licensed under a Creative Commons Attribution (CC-BY) 4.0 License

URL: https://members.oceantrack.org/ipt/resource?r=otnntnuloan-salmonidsintr

Contacts:

Ocean Tracking Network Data Centre
Ocean Tracking Network

Jonathan Pye
Ocean Tracking Network

Jan Grimsrud Davidsen
Norwegian University of Science and Technology

Sindre Håvard Eldøy
Norwegian University of Science and Technology

Lars Rønning
Norwegian University of Science and Technology

Anette Davidsen
Norwegian University of Science and Technology

369,953
occurrence records
2,407
measurements and facts
2
taxa
2
species

Taxa

Missing and invalid fields

Field Missing Invalid
coordinateUncertaintyInMeters 573
0.2%
decimalLatitude 70
0.0%
decimalLongitude 70
0.0%
eventDate 70
0.0%
maximumDepthInMeters 369,953
100.0%
minimumDepthInMeters 369,953
100.0%

Quality flags

The OBIS data quality flags are documented at https://github.com/iobis/obis-qc.

Flag Dropped Records
NO_DEPTH 369,953
100.0%
ON_LAND 34,550
9.3%
NO_COORD 70
0.0%

Measurement types

DNA derived data