Dataset

2011_Warnow: Silver eel migration in the Warnow catchment

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This is an acoustic telemetry dataset containing animal (fish) tracking data collected for the project 2011_Warnow. In total 143 female individuals of Anguilla anguilla and 3 female individuals of Anguilla rostrata in their silver eel stage were captured, tagged and released in late 2011. Data have been standardized to Darwin Core using the etn package and are downsampled to the first detection per hour. The original data are managed in the European Tracking Network Data Platform (https://lifewatch.be/etn/).

Migration patterns of 146 female silver eels on their way through fresh and brackish water stretches of the Warnow River into the Baltic Sea were studied using acoustic telemetry. The majority of eels (77%) regained their expected downstream migration behaviour after a median rehabilitation time of 2 days. Positive rheotactic behaviour was observed for 23% of tagged eels after release, probably influenced by experimental procedures. The observed silver eel escapement rate was 63%. Two migratory groups were classified by significantly different migratory speed, time of residence in brackish waters and biometric silvering characteristics. Although the classification of silvering stages is based on these measures, the proportions of these stages did not reflect the observed differences in migratory behaviour. In the context of a permanent silver eel descent in the freshwater part of the Warnow River, a permanent escapement was likewise occurring into the Baltic Sea.

Citation: Frankowski J, Dorow M, Reckordt M, Ubl C (2026). 2011_Warnow: Silver eel migration in the Warnow catchment. Version 1.4. Flanders Marine Institute. Occurrence dataset. https://doi.org/10.14284/736

Published: June 08, 2026 at 15:49

First registration: April 30, 2026 at 16:00

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

URL: https://ipt.vliz.be/eurobis/resource?r=2011_warnow

Contacts:

Jens Frankowski
Mecklenburg-Vorpommern Research Centre for Agriculture and Fisheries

Malte Dorow
Mecklenburg-Vorpommern Research Centre for Agriculture and Fisheries

Melanie Reckordt
Mecklenburg-Vorpommern Research Centre for Agriculture and Fisheries

Claus Ubl
Deutscher Fischerei-Verband e.V

8,225
occurrence records
292
measurements and facts
2
taxa
2
species

Taxa

Missing and invalid fields

Field Missing Invalid
maximumDepthInMeters 8,225
100.0%
minimumDepthInMeters 8,225
100.0%

Quality flags

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

Flag Dropped Records
NO_DEPTH 8,225
100.0%
ON_LAND 8,224
100.0%

Measurement types

DNA derived data