Tracking the migratory success of stocked European eelsAnguilla anguillain the Baltic Sea
To investigate the extent to which European silver eels Anguilla anguilla, originating from stocking programmes in the Baltic Sea tributaries, effectively contribute to the spawning stock, 274 formerly stocked A. anguilla. emigrating from the Schwentine River near Kiel, Germany, were tagged with T-B...
Published in: | Journal of Fish Biology |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2013
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Subjects: | |
Online Access: | https://doi.org/10.1111/jfb.12032 https://www.openagrar.de/receive/timport_mods_00034612 https://www.openagrar.de/servlets/MCRFileNodeServlet/timport_derivate_00034612/dn051767.pdf |
Summary: | To investigate the extent to which European silver eels Anguilla anguilla, originating from stocking programmes in the Baltic Sea tributaries, effectively contribute to the spawning stock, 274 formerly stocked A. anguilla. emigrating from the Schwentine River near Kiel, Germany, were tagged with T-Bar anchor tags. A total of 29 Anguilla spp. were recaptured (c. 11%) up to 14 months after release. Stocking history of recaptured A. anguilla. was confirmed by otolith microchemistry. Recapture locations were concentrated around the outlet of the Baltic Sea (Danish Belt Sea) with 62% of all recaptures reported here or in the Kattegat. Recaptured Anguilla spp. showed a reduction in both LT and mass (mean±s.d.=-1·5±0·9 cm and -125·3±50·1 g) while average total fat content remained close to values previously reported as high enough to provide energy resources to allow successful completion of the spawning migration (mean±s.d.=28·4±4·4%). The documented mean rate of travel (0·8 kmday-1), however, indicated a delay in the target-oriented migration that might be interpreted as a delayed initial migration phase of orientation towards the exit of the Baltic Sea. |
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