13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria)
Abstract A 13‐year biomonitoring survey was carried out on the European eel, Anguilla anguilla for the first time in North Africa (Algeria) where there is a serious lack of information on the species. The study targeted specimens populating the only four sites where the species is both potentially p...
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Online Access: | http://dx.doi.org/10.1111/jfb.15396 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15396 |
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crwiley:10.1111/jfb.15396 2024-06-23T07:45:34+00:00 13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) Tahri, Mardja Panfili, Jacques 2023 http://dx.doi.org/10.1111/jfb.15396 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15396 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Fish Biology volume 102, issue 6, page 1492-1502 ISSN 0022-1112 1095-8649 journal-article 2023 crwiley https://doi.org/10.1111/jfb.15396 2024-06-04T06:49:12Z Abstract A 13‐year biomonitoring survey was carried out on the European eel, Anguilla anguilla for the first time in North Africa (Algeria) where there is a serious lack of information on the species. The study targeted specimens populating the only four sites where the species is both potentially present and legally exploited (Lake Oubeira, Lake Tonga, Mellah lagoon and Mafragh estuary). A total of 1370 individuals were sampled ranging from 17 to 113 cm in length, 19 to 2642 g in weight and 0.7 months to 6.6 years old, age being estimated from otolith growth marks. Otolith interpretation and age estimation were generally unambiguous at all four sites. According to the EELREP silvering index, the highest proportion of silver females was captured in fresh water (46% in Lake Oubeira and 25% in Lake Tonga), whereas a third were present in brackish water (Mafragh and Mellah). The sex ratio was in favour of females, and silver males were found to mature early (mean length 40 ± 1 cm, mean weight 123 ± 28 g and mean age 2 ± 0.6 years). Growth differed at the four sites, and the growth rate was highest in Lake Oubeira and asymptotic length highest in Mellah lagoon. Metamorphosis from the yellow resident stage to the silver migrating stage occurred very early in the eels' continental life (between 3 and 4 years of age). Results highlight rapid growth in these Algerian sites, and earlier silvering than in eels living in European waters, suggesting different life‐history traits of A. anguilla in North African waters, influenced by environmental conditions. Article in Journal/Newspaper Anguilla anguilla European eel Wiley Online Library Tonga ENVELOPE(7.990,7.990,63.065,63.065) Journal of Fish Biology 102 6 1492 1502 |
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Wiley Online Library |
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crwiley |
language |
English |
description |
Abstract A 13‐year biomonitoring survey was carried out on the European eel, Anguilla anguilla for the first time in North Africa (Algeria) where there is a serious lack of information on the species. The study targeted specimens populating the only four sites where the species is both potentially present and legally exploited (Lake Oubeira, Lake Tonga, Mellah lagoon and Mafragh estuary). A total of 1370 individuals were sampled ranging from 17 to 113 cm in length, 19 to 2642 g in weight and 0.7 months to 6.6 years old, age being estimated from otolith growth marks. Otolith interpretation and age estimation were generally unambiguous at all four sites. According to the EELREP silvering index, the highest proportion of silver females was captured in fresh water (46% in Lake Oubeira and 25% in Lake Tonga), whereas a third were present in brackish water (Mafragh and Mellah). The sex ratio was in favour of females, and silver males were found to mature early (mean length 40 ± 1 cm, mean weight 123 ± 28 g and mean age 2 ± 0.6 years). Growth differed at the four sites, and the growth rate was highest in Lake Oubeira and asymptotic length highest in Mellah lagoon. Metamorphosis from the yellow resident stage to the silver migrating stage occurred very early in the eels' continental life (between 3 and 4 years of age). Results highlight rapid growth in these Algerian sites, and earlier silvering than in eels living in European waters, suggesting different life‐history traits of A. anguilla in North African waters, influenced by environmental conditions. |
format |
Article in Journal/Newspaper |
author |
Tahri, Mardja Panfili, Jacques |
spellingShingle |
Tahri, Mardja Panfili, Jacques 13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
author_facet |
Tahri, Mardja Panfili, Jacques |
author_sort |
Tahri, Mardja |
title |
13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
title_short |
13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
title_full |
13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
title_fullStr |
13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
title_full_unstemmed |
13‐year population survey of the critically endangered European eel in the southern Mediterranean region (Algeria) |
title_sort |
13‐year population survey of the critically endangered european eel in the southern mediterranean region (algeria) |
publisher |
Wiley |
publishDate |
2023 |
url |
http://dx.doi.org/10.1111/jfb.15396 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15396 |
long_lat |
ENVELOPE(7.990,7.990,63.065,63.065) |
geographic |
Tonga |
geographic_facet |
Tonga |
genre |
Anguilla anguilla European eel |
genre_facet |
Anguilla anguilla European eel |
op_source |
Journal of Fish Biology volume 102, issue 6, page 1492-1502 ISSN 0022-1112 1095-8649 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/jfb.15396 |
container_title |
Journal of Fish Biology |
container_volume |
102 |
container_issue |
6 |
container_start_page |
1492 |
op_container_end_page |
1502 |
_version_ |
1802640950690840576 |