"Impact of environmental conditions on the spawning migration of sea trout (Salmo trutta L.) in two large, sub-arctic river systems"

Abstract
The global decline in salmonid stocks has increased the need for knowledge of local adaptations, and life history strategies of salmonids. In this study we used radio-telemetry tracking data from sea trout populations in two large high-latitude rivers to model upstream spawning migration speed of trout in response to prevailing environmental conditions and different stages of the migration. The results indicate that studied populations had similar responses to environmental changes, as trout inhabiting both rivers displayed similar responses to variation in discharge, temperature and migrated distance covered. Higher discharge and temperature had a positive influence on trout migration speed, as did moderate discharge fluctuations. Migration distance influenced movements, as speed increased as trout moved upstream, while speed decreased late in the migration prior to spawning. These results highlight the adaptability of sea trout populations, underlining the importance of stock specific information on habitat use and migration strategies for targeted management.

General information
Title of Dataset: "Impact of environmental conditions on the spawning migration of sea trout (Salmo trutta L.) in two large, sub-arctic river systems"
DOI: 10.17632/6w9c6c7sst.1

Contact Information:
Principal Investigator Contact Information Name: Linus Lähteenmäki
Institution: Åbo Akademi University Address: Aurum, Henriksgatan 2–20520 Åbo, Finland, Email: [e-mail], [e-mail]
ORCID:https://orcid.org/0000-0002-3931-3595

Date of data collection (approximate date): 01-04-2011 - 31-12-2021

Geographic location of data collection: Teno river system (70.5° N, 28.4° E); Tornio river system (65.8° N, 24.1°E)

Dataset includes: Dataset on measured migration speed of sea trout in the two river systems, including environmental and migration characteristics used in the GAMM Analysis (data_large). Environmental data for the study periods to recreate flow and temperature figures (env_data). Population data which include individual fish measurements and migration characteristics (pop_data). Dataset of six individuals to recreate the migration patterns figure of the study (migration_fig).

Recommended citation for this dataset: Lähteenmäki, L., Romakkaniemi, A., Huusko, R., Hellström, G., Orell, P., Erkinaro, J., Rikardsen, A. H., Jensen, J., & Snickars, M. (2026). Data for: "Impact of environmental conditions on the spawning migration of sea trout (Salmo trutta L.) in two large, sub-arctic river systems". Mendeley Data, V1, doi: 10.17632/6w9c6c7sst.1

All datasets used in the data analysis and generation of the visualizations for this study are provided in this repository. Please view the "READ ME" file For more detailed information on dataset contents