Publications des scientifiques de l'IRD

Trape Sébastien, Durand Jean-Dominique, Guilhaumon F., Vigliola Laurent, Panfili Jacques. (2009). Recruitment patterns of young-of-the-year mugilid fishes in a West African estuary impacted by climate change. Estuarine Coastal and Shelf Science, 85 (3), p. 357-367. ISSN 0272-7714.

Titre du document
Recruitment patterns of young-of-the-year mugilid fishes in a West African estuary impacted by climate change
Année de publication
2009
Type de document
Article référencé dans le Web of Science WOS:000272286000002
Auteurs
Trape Sébastien, Durand Jean-Dominique, Guilhaumon F., Vigliola Laurent, Panfili Jacques
Source
Estuarine Coastal and Shelf Science, 2009, 85 (3), p. 357-367 ISSN 0272-7714
With the persistence of the sub-Saharan drought since the 1970s, the Sine Saloum estuary (Senegal) the second largest coastal Biosphere Reserve of West-Africa - has become an "inverse estuary" and hypersaline (salinity> 60) in its upstream part. A one-year survey was conducted from April 2007 to March 2008 at eight sites distributed along the salinity gradient, to investigate the recruitment patterns of young-of-the-year mugilids in such an impacted ecosystem. Fishes were sampled monthly with a conical net and a beach seine in salinities ranging from 31 to 104. Samples were identified to the species level. For the smallest individuals (<20 mm SL) a PCR-RFLP technique, developed on the mitochondrial 16S ribosomal RNA region, was used for identification. A total of 8438 juveniles belonging to six of the eight species of mugilids known for the tropical Eastern Atlantic were collected: Mugil bananensis, Mugil cephalus, Mugil curema, Liza dumerili, Liza falcipinnis and Liza grandisquamis. One species, L dumerili, represented 89% of the total catch. Length-frequency distributions revealed that M. cephalus and L. dumerili preferentially recruited during the dry season whereas the recruitment of M. curema, M. bananensis and L. falcipinnis generally occurred during the wet season. Minimal size at recruitment ranged from 9 to 19 mm SL depending on the species, the smallest size being that of L dumerili. Despite the general salinity increase in the estuary, most parts of the Sine Saloum were suitable for the juveniles. Only the hypersaline area in the uppermost part of the estuary presented very low fish abundance for all species. According to the species, small recruits (12-20 mm SL) were collected at salinities up to 47-78, suggesting that osmoregulatory capacities had been gained early during ontogenesis, possibly resulting from an adaptation of these populations to changing environmental conditions.
Plan de classement
Ecologie, systèmes aquatiques [036]
Description Géographique
SENEGAL
Localisation
Fonds IRD [F B010048429]
Identifiant IRD
fdi:010048429
Contact