@article{fdi:010082198,
  title = {{F}oraging depth depicts resource partitioning and contamination level in a pelagic shark assemblage : insights from mercury stable isotopes},
  author = {{B}esnard, {L}. and {L}e {C}roizier, {G}ael and {G}alvan-{M}agana, {F}. and {P}oint, {D}avid and {K}raffe, {E}. and {K}etchum, {J}. and {R}incon, {R}. {O}. {M}. and {S}chaal, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he decline of shark populations in the world ocean is affecting ecosystem structure and function in an unpredictable way and new ecological information is today needed to better understand the role of sharks in their habitats. {I}n particular, the characterization of foraging patterns is crucial to understand and foresee the evolution of dynamics between sharks and their prey. {M}any shark species use the mesopelagic area as a major foraging ground but the degree to which different pelagic sharks rely on this habitat remains overlooked. {I}n order to depict the vertical dimension of their trophic ecology, we used mercury stable isotopes in the muscle of three pelagic shark species (the blue shark {P}rionace glauca, the shortfin mako shark {I}surus oxyrinchus and the smooth hammerhead shark {S}phyrna zygaena) from the northeastern {P}acific region. {T}he {D}elta {H}g-199 values, ranging from 1.40 to 2.13 parts per thousand in sharks, suggested a diet mostly based on mesopelagic prey in oceanic habitats. {W}e additionally used carbon and nitrogen stable isotopes (delta {C}-13, delta {N}-15) alone or in combination with {D}elta {H}g-199 values, to assess resource partitioning between the three shark species. {A}dding {D}elta {H}g-199 resulted in a decrease in trophic overlap estimates compared to those based on delta {C}-13/delta {N}-15 alone, demonstrating that multi-isotope modeling is needed for accurate trophic description of the three species. {M}ainly, it reveals that they forage at different average depths and that resource partitioning is mostly expressed through the vertical dimension within pelagic shark assemblages. {C}oncomitantly, muscle total mercury concentration ({TH}g) differed between species and increased with feeding depth. {O}verall, this study highlights the key role of the mesopelagic zone for shark species foraging among important depth gradients and reports new ecological information on trophic competition using mercury isotopes. {I}t also suggests that foraging depth may play a pivotal role in the differences between muscle {TH}g from co-occurring high trophic level shark species.},
  keywords = {{T}rophic ecology ; {T}op predator ; {M}ercury stable isotopes ; {R}esource partitioning ; {F}oraging depth ; {M}ercury accumulation ; {MEXIQUE} ; {PACIFIQUE} {NORD} {EST} ; {BASSE} {CALIFORNIE} {PENINSULE} ; {PUNTA} {LOBOS}},
  booktitle = {},
  journal = {{E}nvironmental {P}ollution},
  volume = {283},
  numero = {},
  pages = {117066 [11 p.]},
  ISSN = {0269-7491},
  year = {2021},
  DOI = {10.1016/j.envpol.2021.117066},
  URL = {https://www.documentation.ird.fr/hor/fdi:010082198},
}