Version 1
: Received: 18 October 2023 / Approved: 19 October 2023 / Online: 19 October 2023 (09:37:03 CEST)
Version 2
: Received: 6 March 2024 / Approved: 7 March 2024 / Online: 8 March 2024 (03:39:34 CET)
Version 3
: Received: 1 April 2024 / Approved: 2 April 2024 / Online: 2 April 2024 (10:41:14 CEST)
How to cite:
Rasmussen, G.; Pedersen, M. I.; Therkildsen, B. M. Food, Growth and Biological Production of European eel Anguilla anguilla in a Small Stream in Jutland, Denmark. Preprints2023, 2023101247. https://doi.org/10.20944/preprints202310.1247.v2
Rasmussen, G.; Pedersen, M. I.; Therkildsen, B. M. Food, Growth and Biological Production of European eel Anguilla anguilla in a Small Stream in Jutland, Denmark. Preprints 2023, 2023101247. https://doi.org/10.20944/preprints202310.1247.v2
Rasmussen, G.; Pedersen, M. I.; Therkildsen, B. M. Food, Growth and Biological Production of European eel Anguilla anguilla in a Small Stream in Jutland, Denmark. Preprints2023, 2023101247. https://doi.org/10.20944/preprints202310.1247.v2
APA Style
Rasmussen, G., Pedersen, M. I., & Therkildsen, B. M. (2024). Food, Growth and Biological Production of European eel <em>Anguilla anguilla</em> in a Small Stream in Jutland, Denmark. Preprints. https://doi.org/10.20944/preprints202310.1247.v2
Chicago/Turabian Style
Rasmussen, G., Michael I Pedersen and Birgit M Therkildsen. 2024 "Food, Growth and Biological Production of European eel <em>Anguilla anguilla</em> in a Small Stream in Jutland, Denmark" Preprints. https://doi.org/10.20944/preprints202310.1247.v2
Abstract
Silver eel were sampled in 1981 and 1983 in River Brede, Denmark, with outlet to the North Sea. Yellow eel in River Køge-Lellinge, Denmark, with outlet to the Baltic Sea were sampled 1965-1968. Silver eel were aged by burning the otoliths. Silver male ages varied from 4 to 25 years, lengths 30.8 to 45.3 cm, and female silver eel varied from 7 to 25 years, lengths 42.3 to 77.3 cm. von Bertalanffy trajectories of length-at-age of male and female yellow eel were calculated in both rivers. Younger yellow eel had significantly higher annual growth rate compared to older age groups, and females grew significantly faster than males. Two models for natural mortality M were used to estimate number of glass eel needed to produce number of silver eel for each sex and silver age group. Annual silver eel production from River Brede Å was 49.2 kg ha-1, demanding 2,894 glass eel ha-1 and in River Køge-Lellinge, the silver eel production was 48.5 kg ha-1, demanding 5,570 glass eel ha-1. It was calculated that one (0.29 g) thousand glass eel contribute to 8.8 kg silver eel in River Køge-Lellinge, and 17.0 kg silver eel in River Brede. To fulfill the Danish EMP in rivers requires annual stocking of 33 tons or 9.4 million reared on-grown eel (3.5 g) to compensate for 183 tons lost silver eel.
Keywords
otolith; ageing; natural mortality; linear growth; growth rate; silver eel production; biological production of yellow eel; von Bertalanffy; EMP; stocking
Subject
Biology and Life Sciences, Aquatic Science
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.