[article] 
inAr Vran > vol. 24 n°2 (2013) . - pp. 42-46

Titre :	Histoire de vie et connectivité entre habitats essentiels de 3 espèces de lançons, approche par les marqueurs environnementaux
Type de document :	texte imprimé
Auteurs :	Flora Laugier, Auteur ; Eric Feunteun, Auteur ; Alexandre Carpentier, Auteur
Année de publication :	2013
Article en page(s) :	pp. 42-46
Langues :	Français (fre)
Résumé :	Although sandeels are intermediate species in marine food webs and an important trophic source for many predators (fishes, birds and marine mammals), their ecology remains relatively poorly known. Variation in stocks of sandeel can have notably major effects on the breeding success and survival of their predators. They spend a lot of time buried dormant in sand, venturing out only to feed in the water column at different time scales (daily, seasonal, life cycle). Even if very coarse sand banks are often described as their favorite habitats, the potential distinction between Essential Ecological Habitats (EEH: spawning, feeding, resting and nursery habitats) has still not been studied. Consequently, we aimed to better understand sandeel’s life history and the use of intertidal and subtidal sand habitats through environmental tracers such as otolith elemental fingerprint and stable isotopes (δ13C and δ15N in muscle). Connectivity hypothesis between habitats are explored comparing microchemistry fingerprints from the center to the edge of otoliths. Samplings in intertidal and subtidal areas show different specific composition and age structure. We sampled four species of sandeels (Ammodytes tobianus, Hyperoplus lanceolatus, Hyperoplus immaculatus and Gymnammodytes semisquamatus) among five reported in the Normand-Breton Gulf by Le Mao (2009) and focused on Hyperoplus for analyses. Otolith’s fingerprints suggest that most H. immaculatus use both intertidal and subtidal habitats during their life, although this species appeared more abundant in subtidal sites. More precisely, the first life stages (i.e. larval and juvenile) of both Hyperoplus species seem to occur in intertidal zones suggesting that very coarse sand beaches serve as nursery and maybe spawning habitats. Stable isotopes showed strong 15N enrichment in H. lanceolatus muscle tissues, indicating an upper trophic level for this species, which could be a predator to other sandeel species. Finally, we highlight that these sympatric species have contrasted ecology with regard to their trophic level, life history or spatial distribution and could inhabit different habitats during their life.
Type de document :	Périodique
Permalink :	https://pmb.bretagne-vivante.org/pmb/opac_css/index.php?lvl=notice_display&id=64

[article] Histoire de vie et connectivité entre habitats essentiels de 3 espèces de lançons, approche par les marqueurs environnementaux [texte imprimé] / Flora Laugier, Auteur ; Eric Feunteun, Auteur ; Alexandre Carpentier, Auteur . - 2013 . - pp. 42-46.
Langues : Français (fre)
in Ar Vran > vol. 24 n°2 (2013) . - pp. 42-46

Résumé :	Although sandeels are intermediate species in marine food webs and an important trophic source for many predators (fishes, birds and marine mammals), their ecology remains relatively poorly known. Variation in stocks of sandeel can have notably major effects on the breeding success and survival of their predators. They spend a lot of time buried dormant in sand, venturing out only to feed in the water column at different time scales (daily, seasonal, life cycle). Even if very coarse sand banks are often described as their favorite habitats, the potential distinction between Essential Ecological Habitats (EEH: spawning, feeding, resting and nursery habitats) has still not been studied. Consequently, we aimed to better understand sandeel’s life history and the use of intertidal and subtidal sand habitats through environmental tracers such as otolith elemental fingerprint and stable isotopes (δ13C and δ15N in muscle). Connectivity hypothesis between habitats are explored comparing microchemistry fingerprints from the center to the edge of otoliths. Samplings in intertidal and subtidal areas show different specific composition and age structure. We sampled four species of sandeels (Ammodytes tobianus, Hyperoplus lanceolatus, Hyperoplus immaculatus and Gymnammodytes semisquamatus) among five reported in the Normand-Breton Gulf by Le Mao (2009) and focused on Hyperoplus for analyses. Otolith’s fingerprints suggest that most H. immaculatus use both intertidal and subtidal habitats during their life, although this species appeared more abundant in subtidal sites. More precisely, the first life stages (i.e. larval and juvenile) of both Hyperoplus species seem to occur in intertidal zones suggesting that very coarse sand beaches serve as nursery and maybe spawning habitats. Stable isotopes showed strong 15N enrichment in H. lanceolatus muscle tissues, indicating an upper trophic level for this species, which could be a predator to other sandeel species. Finally, we highlight that these sympatric species have contrasted ecology with regard to their trophic level, life history or spatial distribution and could inhabit different habitats during their life.
Type de document :	Périodique
Permalink :	https://pmb.bretagne-vivante.org/pmb/opac_css/index.php?lvl=notice_display&id=64