Observations on movements of yellow eels, Anguilla anguilla L., after displacement from coastal waters to sea
Four groups of yellow eels, three from three Po Delta brackish bays (Pila, Scardovari and Goro) and one from the French Atlantic coast, were marked by freeze‐branding and released at an open‐sea point 5 miles offshore. Of the 2137 eels released, 453 (21.2%) were recaptured over a 1‐month period. The...
Published in: | Journal of Fish Biology |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1987
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Subjects: | |
Online Access: | http://dx.doi.org/10.1111/j.1095-8649.1987.tb05222.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1987.tb05222.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1987.tb05222.x |
Summary: | Four groups of yellow eels, three from three Po Delta brackish bays (Pila, Scardovari and Goro) and one from the French Atlantic coast, were marked by freeze‐branding and released at an open‐sea point 5 miles offshore. Of the 2137 eels released, 453 (21.2%) were recaptured over a 1‐month period. The percentage recaptured is not independent of either fish size (the larger eels being recaptured in greater quantity than the smaller ones which are supposed to be less catchable and more easily overlooked by fishermen) or fish origin (the recapture rate of the French stock was both the lowest, at 9.8%, and the most dispersed in time and space). The highest multiple catches were for eels from Pila and Scardovari and were made in the first days of the experiment. Of the recaptured eels, 75% were caught in the inland water closest (9 km) to the release point; only 8.6% were recaptured at the mouth of the two branches of the River Po. There is no evidence of a real homing tendency for yellow eels previously adapted to living in brackish water: the massive return to the nearest coast is probably only an avoidance reaction to the unfavourable open‐sea environment. |
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