On the significance of Antarctic jellyfish as food for Adélie penguins, as revealed by video loggers

• Published in: Marine Biology
• Main Authors: Thiebot, Jean-Baptiste, Ito, Kentaro, Raclot, Thierry, Poupart, Timothée, Kato, Akiko, Ropert‐coudert, Yan, Takahashi, Akinori
• Other Authors: National Insitute of Polar Research, National Institute of Polar Research Tokyo (NiPR), Department of Polar Science, Graduate University for Advanced Sciences, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), IPEV (program#1091);Zone Atelier Antarctique (CNRS);WWF-UK;Japan Society for the Promotion of Science
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: [SDE]Environmental Sciences; Antarctic; Dumont d’Urville; Antarc*; Sea ice
• Online Access: https://hal.science/hal-01310419; https://doi.org/10.1007/s00227-016-2890-2

International audience Concern of pelagic gelatinous organisms takingover perturbed marine ecosystems has led to a recentincrease in research into this group. However, the significanceof this group as prey remains challenging to assess,and hence, gelatinous consumers are often depicted incorrectlyas dead ends of pelagic food webs. In the SouthernOcean, where a shift in trophic webs may favour gelatinousanimals, we video-monitored prey intake of a key predator.Twenty-eight chick-rearing Adélie penguins Pygoscelisadeliae from Dumont d’Urville station (66°40′S,140°01′E) were instrumented with miniaturized videologgers in 2014–2015. Among other items (krill, fish),101 gelatinous organisms (n = 79 jellyfish, 6 salps and 16unidentified) were observed on 13 of 21 exploitable video footages (total: 59 h). Importantly, 65.3 % of gelatinousorganisms were attacked, but among them salps were notattacked. Attacks on jellyfish were significantly associatedwith the visible presence of the jellyfish’s gonad. Jellyfishwere encountered at an average depth of 26.2 ± 10.4 m,significantly shallower than krill. Attacks occurred mostlyduring bottom, but also descent or ascent dive phases. ConcomitantGPS location for four birds revealed that attackson jellyfish occurred above the shelf, 35 km north from thecolony, where sea ice concentration reached 88 %. Theseresults indicate that Adélie penguins occasionally feedon jellyfish, even though other prey types are also available.Refining our perception of scyphozoans’ niche maythus help anticipate the functional response of the foodwebs to the extensive changes witnessed in the Antarcticenvironment.