caa a22 4500 445819162 CHVBK 20180317145238.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s00338-010-0680-8 doi (NATIONALLICENCE)springer-10.1007/s00338-010-0680-8 Isotopic signatures, foraging habitats and trophic relationships between fish and seasnakes on the coral reefs of New Caledonia [Elektronische Daten] [F. Brischoux, X. Bonnet, Y. Cherel, R. Shine] A predator's species, sex and body size can influence the types of prey that it consumes, but why? Do such dietary divergences result from differences in foraging habitats, or reflect differential ability to locate, capture or ingest different types of prey? That question is difficult to answer if foraging occurs in places that preclude direct observation. In New Caledonia, amphibious sea kraits (Laticauda laticaudata and L. saintgironsi) mostly eat eels—but the species consumed differ between snake species and vary with snake body size and sex. Because the snakes capture eels within crevices on the sea floor, it is not possible to observe snake foraging on any quantitative basis. We used stable isotopes to investigate habitat-divergence and ontogenetic shifts in feeding habits of sympatric species of sea kraits. Similarities in δ15N (~10.5‰) values suggest that the two snake species occupy similar trophic levels in the coral-reef foodweb. However, δ13C values differed among the eight eel species consumed by snakes, as well as between the two snake species, and were linked to habitat types. Specifically, δ13C differed between soft- vs. hard-substrate eel species, and consistently differed between the soft-bottom forager L. laticaudata (~ −14.7‰) and the hard-bottom forager L. saintgironsi (~ −12.5‰). Differences in isotopic signatures within and between the two sea krait species and their prey were consistent with the hypothesis of habitat-based dietary divergence. Isotopic composition varied with body size within each of the snake species and varied with body size within some eel species, reflecting ontogenetic shifts in feeding habits of both the sea kraits and their prey. Our results support the findings of previous studies based on snake stomach contents, indicating that further studies could usefully expand these isotopic analyses to a broader range of trophic levels, fish species and spatial scales. Springer-Verlag, 2010 Anguilliform fish nationallicence Coral reefs nationallicence Sea kraits nationallicence Stable isotopes nationallicence Brischoux F. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut Bonnet X. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut Cherel Y. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut Shine R. School of Biological Sciences A08, University of Sydney, 2006, Sydney, NSW, Australia aut Coral Reefs Springer-Verlag 30/1(2011-03-01), 155-165 0722-4028 30:1<155 2011 30 338 https://doi.org/10.1007/s00338-010-0680-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00338-010-0680-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Brischoux F. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut NATIONALLICENCE 700 1- Bonnet X. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut NATIONALLICENCE 700 1- Cherel Y. Centre d'Etudes Biologiques de Chizé, UPR 1934 du CNRS, 79360, Villiers en Bois, France aut NATIONALLICENCE 700 1- Shine R. School of Biological Sciences A08, University of Sydney, 2006, Sydney, NSW, Australia aut NATIONALLICENCE 773 0- Coral Reefs Springer-Verlag 30/1(2011-03-01), 155-165 0722-4028 30:1<155 2011 30 338 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer