Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure
International audience Identifying factors influencing survivorship is key to understanding population persistence. Although satellite telemetry is a powerful tool for studying remote animal ecology and behaviour it is rarely used for demographic studies because distinguishing the death of the anima...
Published in: | Frontiers in Marine Science |
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Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2020
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Online Access: | https://hal.science/hal-03007043 https://hal.science/hal-03007043/document https://hal.science/hal-03007043/file/HFMS7_2020.pdf https://doi.org/10.3389/fmars.2020.517901 |
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ftunivrochelle:oai:HAL:hal-03007043v1 2024-02-11T10:03:30+01:00 Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure Henderson, Angus, F Mcmahon, Clive, R Harcourt, Rob Guinet, Christophe Picard, Baptiste Wotherspoon, Simon Hindell, Mark, A College of Sciences and Engineering Australia University of Tasmania Hobart, Australia (UTAS) 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) 2020-09-24 https://hal.science/hal-03007043 https://hal.science/hal-03007043/document https://hal.science/hal-03007043/file/HFMS7_2020.pdf https://doi.org/10.3389/fmars.2020.517901 en eng HAL CCSD Frontiers Media info:eu-repo/semantics/altIdentifier/doi/10.3389/fmars.2020.517901 hal-03007043 https://hal.science/hal-03007043 https://hal.science/hal-03007043/document https://hal.science/hal-03007043/file/HFMS7_2020.pdf doi:10.3389/fmars.2020.517901 info:eu-repo/semantics/OpenAccess ISSN: 2296-7745 Frontiers in Marine Science https://hal.science/hal-03007043 Frontiers in Marine Science, 2020, 7, ⟨10.3389/fmars.2020.517901⟩ satellite telemetry Southern Ocean ARGOS Mirounga leonina survival % migration SES IMOS animal tracking facility [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2020 ftunivrochelle https://doi.org/10.3389/fmars.2020.517901 2024-01-23T23:34:51Z International audience Identifying factors influencing survivorship is key to understanding population persistence. Although satellite telemetry is a powerful tool for studying remote animal ecology and behaviour it is rarely used for demographic studies because distinguishing the death of the animal (individual mortality) from failure of the tag (mechanical tag failure) has proven difficult. Southern elephant seals present an opportunity to separate tag failure from animal mortality thanks to the availability of large tracking datasets, broad knowledge of demographic rates, and because for these large animals, satellite tags are known not to influence mortality rates. A key rationale for investigating satellite telemetry to estimate mortality as compared to using traditional Capture-Mark-Recapture methods is the potential for obtaining spatially and temporally specific information, particularly while the animals are at sea and largely unobservable. We used satellite tag data from 182 seals from Isles Kerguelen, deployed between 2004 and 2018. Of these, 76 (42%) tags transmitted for the full post-moult foraging trip (max. 265 days for females and max. 305 days for sub-adult males) with the remaining 107 tags (58%) ceasing transmission at sea. We found that contrary to expectations, behavioural choices seem not to influence tag failure rates by mechanical means, rather the signals we detected seemed to align with previously described variation in mortality between groups. There was evidence, albeit limited, for an increase in tag failure for adult females in years with negative Southern Annular Mode (lower Southern Ocean productivity). We speculate that this increase in failure may suggest higher mortality in these years. Also, males using the Kerguelen Plateau had higher tag failure rates than those in the sea-ice zone, perhaps indicative of higher mortality. We suspect that these differences in tag failure rates between groups reflect variation in predator exposure and foraging success. This suggests ... Article in Journal/Newspaper Elephant Seal Elephant Seals Mirounga leonina Sea ice Southern Elephant Seal Southern Elephant Seals Southern Ocean HAL - Université de La Rochelle Kerguelen Southern Ocean Frontiers in Marine Science 7 |
institution |
Open Polar |
collection |
HAL - Université de La Rochelle |
op_collection_id |
ftunivrochelle |
language |
English |
topic |
satellite telemetry Southern Ocean ARGOS Mirounga leonina survival % migration SES IMOS animal tracking facility [SDE]Environmental Sciences |
spellingShingle |
satellite telemetry Southern Ocean ARGOS Mirounga leonina survival % migration SES IMOS animal tracking facility [SDE]Environmental Sciences Henderson, Angus, F Mcmahon, Clive, R Harcourt, Rob Guinet, Christophe Picard, Baptiste Wotherspoon, Simon Hindell, Mark, A Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
topic_facet |
satellite telemetry Southern Ocean ARGOS Mirounga leonina survival % migration SES IMOS animal tracking facility [SDE]Environmental Sciences |
description |
International audience Identifying factors influencing survivorship is key to understanding population persistence. Although satellite telemetry is a powerful tool for studying remote animal ecology and behaviour it is rarely used for demographic studies because distinguishing the death of the animal (individual mortality) from failure of the tag (mechanical tag failure) has proven difficult. Southern elephant seals present an opportunity to separate tag failure from animal mortality thanks to the availability of large tracking datasets, broad knowledge of demographic rates, and because for these large animals, satellite tags are known not to influence mortality rates. A key rationale for investigating satellite telemetry to estimate mortality as compared to using traditional Capture-Mark-Recapture methods is the potential for obtaining spatially and temporally specific information, particularly while the animals are at sea and largely unobservable. We used satellite tag data from 182 seals from Isles Kerguelen, deployed between 2004 and 2018. Of these, 76 (42%) tags transmitted for the full post-moult foraging trip (max. 265 days for females and max. 305 days for sub-adult males) with the remaining 107 tags (58%) ceasing transmission at sea. We found that contrary to expectations, behavioural choices seem not to influence tag failure rates by mechanical means, rather the signals we detected seemed to align with previously described variation in mortality between groups. There was evidence, albeit limited, for an increase in tag failure for adult females in years with negative Southern Annular Mode (lower Southern Ocean productivity). We speculate that this increase in failure may suggest higher mortality in these years. Also, males using the Kerguelen Plateau had higher tag failure rates than those in the sea-ice zone, perhaps indicative of higher mortality. We suspect that these differences in tag failure rates between groups reflect variation in predator exposure and foraging success. This suggests ... |
author2 |
College of Sciences and Engineering Australia University of Tasmania Hobart, Australia (UTAS) 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) |
format |
Article in Journal/Newspaper |
author |
Henderson, Angus, F Mcmahon, Clive, R Harcourt, Rob Guinet, Christophe Picard, Baptiste Wotherspoon, Simon Hindell, Mark, A |
author_facet |
Henderson, Angus, F Mcmahon, Clive, R Harcourt, Rob Guinet, Christophe Picard, Baptiste Wotherspoon, Simon Hindell, Mark, A |
author_sort |
Henderson, Angus, F |
title |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
title_short |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
title_full |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
title_fullStr |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
title_full_unstemmed |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
title_sort |
inferring variation in southern elephant seal at-sea mortality by modelling tag failure |
publisher |
HAL CCSD |
publishDate |
2020 |
url |
https://hal.science/hal-03007043 https://hal.science/hal-03007043/document https://hal.science/hal-03007043/file/HFMS7_2020.pdf https://doi.org/10.3389/fmars.2020.517901 |
geographic |
Kerguelen Southern Ocean |
geographic_facet |
Kerguelen Southern Ocean |
genre |
Elephant Seal Elephant Seals Mirounga leonina Sea ice Southern Elephant Seal Southern Elephant Seals Southern Ocean |
genre_facet |
Elephant Seal Elephant Seals Mirounga leonina Sea ice Southern Elephant Seal Southern Elephant Seals Southern Ocean |
op_source |
ISSN: 2296-7745 Frontiers in Marine Science https://hal.science/hal-03007043 Frontiers in Marine Science, 2020, 7, ⟨10.3389/fmars.2020.517901⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3389/fmars.2020.517901 hal-03007043 https://hal.science/hal-03007043 https://hal.science/hal-03007043/document https://hal.science/hal-03007043/file/HFMS7_2020.pdf doi:10.3389/fmars.2020.517901 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3389/fmars.2020.517901 |
container_title |
Frontiers in Marine Science |
container_volume |
7 |
_version_ |
1790599761966923776 |