Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability
Because time-series relative to foraging ecology, environmental parameters and population trends are scarce, few studies focused on the mechanisms linking oceanographic variables with the foraging behaviour and breeding success in marine top predators. This PhD thesis aims to assess the effects of i...
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Other Authors: | , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
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HAL CCSD
2020
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Subjects: | |
Online Access: | https://theses.hal.science/tel-03371309 https://theses.hal.science/tel-03371309v2/document https://theses.hal.science/tel-03371309v2/file/MESTRE_Julie_2020.pdf |
id |
ftunivrochelle:oai:HAL:tel-03371309v2 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
HAL - Université de La Rochelle |
op_collection_id |
ftunivrochelle |
language |
French |
topic |
Foraging ecology Bio-logging Stable isotopes Foraging strategies Breeding success Southern elephant seals Écologie alimentaire Télémétrie Isotopes stables Stratégies alimentaires Succès reproducteur Éléphants de mer austraux [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology |
spellingShingle |
Foraging ecology Bio-logging Stable isotopes Foraging strategies Breeding success Southern elephant seals Écologie alimentaire Télémétrie Isotopes stables Stratégies alimentaires Succès reproducteur Éléphants de mer austraux [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology Mestre, Julie Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
topic_facet |
Foraging ecology Bio-logging Stable isotopes Foraging strategies Breeding success Southern elephant seals Écologie alimentaire Télémétrie Isotopes stables Stratégies alimentaires Succès reproducteur Éléphants de mer austraux [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology |
description |
Because time-series relative to foraging ecology, environmental parameters and population trends are scarce, few studies focused on the mechanisms linking oceanographic variables with the foraging behaviour and breeding success in marine top predators. This PhD thesis aims to assess the effects of inter-annual environmental conditions and individual strategies on the foraging ecology and breeding success of the southern elephant seal (Mirounga leonina), a key species of the Southern Ocean. The simultaneous analysis of stable isotopes and tracking-diving time-series highlighted that the foraging habitats, as well as the diving- and foraging behaviour of female seals, remained stable over the last fourteen years. This thesis also revealed a consistency in the Antarctic and sub-Antarctic foraging strategies, and a decrease in the body condition of females exploiting the latter habitat. The weaning mass of their pups, considered as a proxy of the breeding success, decreased too. A difference in habitat quality was detected between the area located east and west of the Kerguelen archipelago, with the area located west providing a higher foraging success. Moreover, a spatial structuration of foraging strategies was highlighted between two breeding sites located at Kerguelen Island. Despite consistency in the behaviour of seals, an overall increase in body condition was assessed over the study period. Combined with a global decrease in δ13C values, this result suggests that some modifications are occurring in the food web of the Southern Ocean. En raison du manque de séries temporelles associant écologie en mer, paramètres océanographiques, et trajectoires démographiques, peu d’études se sont intéressées aux mécanismes reliant conditions océanographiques, succès alimentaire à l’échelle des trajets en mer, et succès reproducteur associé chez des prédateurs marins. Le présent travail de thèse propose de déterminer l’effet de la variabilité interannuelle des paramètres environnementaux, ainsi que des stratégies ... |
author2 |
Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Sorbonne Université Jean-Benoît Charrassin |
format |
Doctoral or Postdoctoral Thesis |
author |
Mestre, Julie |
author_facet |
Mestre, Julie |
author_sort |
Mestre, Julie |
title |
Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
title_short |
Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
title_full |
Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
title_fullStr |
Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
title_full_unstemmed |
Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability |
title_sort |
impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from kerguelen islands : influence of individual strategies and inter-annual variability |
publisher |
HAL CCSD |
publishDate |
2020 |
url |
https://theses.hal.science/tel-03371309 https://theses.hal.science/tel-03371309v2/document https://theses.hal.science/tel-03371309v2/file/MESTRE_Julie_2020.pdf |
long_lat |
ENVELOPE(69.500,69.500,-49.250,-49.250) |
geographic |
Antarctic Southern Ocean The Antarctic Kerguelen Kerguelen Islands Kerguelen Island |
geographic_facet |
Antarctic Southern Ocean The Antarctic Kerguelen Kerguelen Islands Kerguelen Island |
genre |
Antarc* Antarctic Elephant Seal Elephant Seals Kerguelen Islands Mirounga leonina Southern Elephant Seal Southern Elephant Seals Southern Ocean |
genre_facet |
Antarc* Antarctic Elephant Seal Elephant Seals Kerguelen Islands Mirounga leonina Southern Elephant Seal Southern Elephant Seals Southern Ocean |
op_source |
https://theses.hal.science/tel-03371309 Biodiversité et Ecologie. Sorbonne Université, 2020. Français. ⟨NNT : 2020SORUS228⟩ |
op_relation |
NNT: 2020SORUS228 tel-03371309 https://theses.hal.science/tel-03371309 https://theses.hal.science/tel-03371309v2/document https://theses.hal.science/tel-03371309v2/file/MESTRE_Julie_2020.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1790607873536950272 |
spelling |
ftunivrochelle:oai:HAL:tel-03371309v2 2024-02-11T09:57:01+01:00 Impacts of environmental parameters on the foraging behaviour and breeding success of southern elephant seals from Kerguelen Islands : influence of individual strategies and inter-annual variability Entre variabilité interannuelle et stratégies individuelles : effets des paramètres environnementaux sur l’écologie alimentaire et le succès reproducteur des éléphants de mer de l’archipel de Kerguelen Mestre, Julie Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) Sorbonne Université Jean-Benoît Charrassin 2020-12-18 https://theses.hal.science/tel-03371309 https://theses.hal.science/tel-03371309v2/document https://theses.hal.science/tel-03371309v2/file/MESTRE_Julie_2020.pdf fr fre HAL CCSD NNT: 2020SORUS228 tel-03371309 https://theses.hal.science/tel-03371309 https://theses.hal.science/tel-03371309v2/document https://theses.hal.science/tel-03371309v2/file/MESTRE_Julie_2020.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-03371309 Biodiversité et Ecologie. Sorbonne Université, 2020. Français. ⟨NNT : 2020SORUS228⟩ Foraging ecology Bio-logging Stable isotopes Foraging strategies Breeding success Southern elephant seals Écologie alimentaire Télémétrie Isotopes stables Stratégies alimentaires Succès reproducteur Éléphants de mer austraux [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology info:eu-repo/semantics/doctoralThesis Theses 2020 ftunivrochelle 2024-01-23T23:34:36Z Because time-series relative to foraging ecology, environmental parameters and population trends are scarce, few studies focused on the mechanisms linking oceanographic variables with the foraging behaviour and breeding success in marine top predators. This PhD thesis aims to assess the effects of inter-annual environmental conditions and individual strategies on the foraging ecology and breeding success of the southern elephant seal (Mirounga leonina), a key species of the Southern Ocean. The simultaneous analysis of stable isotopes and tracking-diving time-series highlighted that the foraging habitats, as well as the diving- and foraging behaviour of female seals, remained stable over the last fourteen years. This thesis also revealed a consistency in the Antarctic and sub-Antarctic foraging strategies, and a decrease in the body condition of females exploiting the latter habitat. The weaning mass of their pups, considered as a proxy of the breeding success, decreased too. A difference in habitat quality was detected between the area located east and west of the Kerguelen archipelago, with the area located west providing a higher foraging success. Moreover, a spatial structuration of foraging strategies was highlighted between two breeding sites located at Kerguelen Island. Despite consistency in the behaviour of seals, an overall increase in body condition was assessed over the study period. Combined with a global decrease in δ13C values, this result suggests that some modifications are occurring in the food web of the Southern Ocean. En raison du manque de séries temporelles associant écologie en mer, paramètres océanographiques, et trajectoires démographiques, peu d’études se sont intéressées aux mécanismes reliant conditions océanographiques, succès alimentaire à l’échelle des trajets en mer, et succès reproducteur associé chez des prédateurs marins. Le présent travail de thèse propose de déterminer l’effet de la variabilité interannuelle des paramètres environnementaux, ainsi que des stratégies ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Elephant Seal Elephant Seals Kerguelen Islands Mirounga leonina Southern Elephant Seal Southern Elephant Seals Southern Ocean HAL - Université de La Rochelle Antarctic Southern Ocean The Antarctic Kerguelen Kerguelen Islands Kerguelen Island ENVELOPE(69.500,69.500,-49.250,-49.250) |