Monitoring Atlantic salmon (Salmo salar) smolt migration in a large river system using environmental DNA
Data files
Apr 09, 2025 version files 22.70 KB
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modelling_data.xlsx
19.87 KB
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README.md
2.83 KB
Abstract
Effective monitoring strategies are key for aquatic species conservation, but traditional methods often require significant resources, especially in large aquatic systems. The emergence of quantitative environmental DNA (eDNA) is a promising alternative. Yet, few studies have evaluated the possibility of quantifying Atlantic salmon abundance with eDNA when individuals are at low abundance and occur in large river systems. In this study, we tested the efficacy of eDNA to monitor and quantify daily variation in smolts counts during their downstream migration in a large river system with low abundance of smolts. During the 2021 and 2022 downstream migrations, trap nets were used to conduct a daily census of smolts in the Romaine and Puyjalon rivers (Québec, Canada) while eDNA samples were collected daily over a transect perpendicular to the riverbank. Using quantitative real-time qPCR, we showed that discharge-corrected eDNA concentrations were positively correlated with daily smolt counts for both years. In addition, we found that controlling for temperature and precipitation improved model transferability between years, showing the importance of considering environmental correlates when using eDNA for abundance quantification. Finally, smolt counts were correlated with eDNA concentrations on the same day, but not with eDNA concentrations one or two days prior, highlighting the capacity of the model to track daily fluctuations in smolt abundance. Our results underscore the potential of using eDNA to monitor Atlantic salmon in large river systems with low smolt abundance when the river hydrology and environmental conditions are documented.
Dataset DOI: 10.5061/dryad.mw6m9067j
Description of the data and file structure
We provide here the complete data set we used in our article : Monitoring Atlantic Salmon (Salmo salar) Smolt Migration in a Large River System Using Environmental DNA.
You will find three sheets in the excel. The first one describe all variable present in the study along with their unit and transformation. Second sheet is the dataset we used to predict capture with eDNA modified concentration. Finally, the third one is the complete capture of smolts before, during and after eDNA sampling used for Figure 2 in the article.
Files and variables
File: modelling_data.xlsx
Description: Data used for the study. Variables are describe below with unit in bracket.
Variables
Variable | Unit | Description | ||
---|---|---|---|---|
Date | none | Date of sampling of smolts and eDNA | ||
Jour | none | Date without the year | ||
Year | none | Year of sampling | ||
Caughts | none | Number of smolts caught each day | ||
Discharge | m3/s | Mean Flowate for the Day | ||
T | °C | Mean Temperature for the Day | ||
Precip | mm | Mean Precipitation for the Day | ||
C_cover | % | Mean Cloud Cover for the Day | ||
S_energy | MJ/m2 | Mean Solar Energy for the Day | ||
eDNA | copy/L | Mean eDNA concentration calculated from each eDNA sampling from one day (see Materials and Methods) | ||
C_eDNA | copy/s | Corrected eDNA concentration with the flowrate (eDNAc = (log10(eDNA)*Discharge)/1000 |
Code/software
All analysis were performed in R software (version 4.2) and are described in the materials and methods section of the article.