FN Archimer Export Format
PT J
TI Stable isotopes reveal the trophic position and mesopelagic fish diet of female southern elephant seals breeding on the Kerguelen Islands
BT 
AF CHEREL, Y
   DUCATEZ, S
   FONTAINE, C
   RICHARD, Patrice
   GUINET, C
AS 1:1;2:1;3:1;4:2;5:1;
FF 1:;2:;3:;4:PDG-DOP-DCB-BM;5:;
C1 CNRS, Ctr Etud Biol Chize, UPR 1934, F-79360 Villiers En Bois, France.
   CNRS IFREMER ULR, Ctr Rech Ecosyst Littoraux Anthropises, UMR 6217, F-17137 Lhoumeau, France.
C2 CNRS, FRANCE
   IFREMER, FRANCE
SI NANTES
SE PDG-DOP-DCB-BM
IN WOS Ifremer jusqu'en 2018
   copubli-france
IF 2.631
TC 146
UR https://archimer.ifremer.fr/doc/2008/publication-5021.pdf
LA English
DT Article
DE ;Squid;Southern Ocean;Pelagic ecosystem;Myctophid;Mesopelagic fish;Cephalopod
AB Trophic interactions between organisms are the main drivers of ecosystem dynamics, but scant dietary information is available for wide-ranging predators during migration. We investigated feeding habits of a key consumer of the Southern Ocean, the southern elephant seal Miroungia leonina, by comparing its blood delta(13) C and delta N-15 values with those of various marine organisms, including crustaceans, squid, fishes, seabirds and fur seals. At the end of winter, delta C-13 values (-23.1 to -20.1 parts per thousand)indicate that female elephant seals forage mainly in the vicinity of the Polar Front and in the Polar Frontal Zone. Trophic levels derived from delta N-15 values (trophic level = 4.6) show that the southern elephant seal is a top consumer in the pelagic ecosystem that is dominated by colossal squid. The mean delta N-15 value of seals (10.1 +/- 0.3 parts per thousand) indicates that they are not crustacean eaters, but instead feed on crustacean-eating prey. Surprisingly, most of the previously identified prey species have isotope delta C-13 and delta N-15 values that do not fit with those of potential food items. The most singular pattern to emerge from delta N-15 values of predators and prey is that female seals are likely to feed on myctophid fishes, not squid or Patagonian toothfish. We therefore suggest that they Occupy a unique trophic niche amongst the guild of air-breathing, diving vertebrates by feeding on mesopelagic fish at great depths. In turn, this finding emphasizes the role of myctophids in oceanic waters and will help to quantify and model fluxes of matter and energy within the pelagic ecosystem of the Southern Ocean.
PY 2008
PD OCT
SO Marine Ecology Progress Series
SN 0171-8630
PU Inter-Research
VL 370
UT 000261229600019
BP 239
EP 247
DI 10.3354/meps07673
ID 5021
ER

EF