{"doi":"10.1242/jeb.118109","title":"Fishing for drifts: detecting buoyancy changes of a top marine predator using a step-wise filtering method","abstract":"<jats:p>In southern elephant seals (Mirounga leonina), fasting and foraging related fluctuations in body composition are reflected by buoyancy changes. Such buoyancy changes can be monitored by measuring changes in the rate at which a seal drifts passively through the water column, i.e. when all active swimming motion ceases. Here, we present an improved knowledge-based method for detecting buoyancy changes from compressed and abstracted dive profiles received through telemetry. By step-wise filtering of the dive data, the developed algorithm identifies fragments of dives that correspond to times when animals drift. In the dive records of eleven southern elephant seals from South Georgia, this filtering method identified 0.8% to 2.2% of all dives as drift dives, indicating large individual variation in drift diving behaviour. The obtained drift rate time series exhibit that, at the beginning of each migration, all individuals were strongly negatively buoyant. Over the following 75 to 150 days, the buoyancy of all individuals peaked close to or at neutral buoyancy, indicative of a seal's foraging success. Independent verification with visually inspected detailed high-resolution dive data confirmed that this method is capable of reliably detecting buoyancy changes in the dive records of drift diving species using abstracted data. This also affirms that abstracted dive profiles convey the geometric shape of drift dives in sufficient detail for them to be identified. Further, it suggest that, using this step-wise filtering method, buoyancy changes could be detected even in old datasets with compressed dive information, for which conventional drift dive classification previously failed.</jats:p>","journal":"Journal of Experimental Biology","year":2015,"id":31361,"datarank":0.7578309923747637,"base_score":2.5649493574615367,"endowment":2.5649493574615367,"self_citation_contribution":0.38474240361923057,"citation_network_contribution":0.3730885887555332,"self_endowment_contribution":0.38474240361923057,"citer_contribution":0.3730885887555332,"corpus_percentile":null,"corpus_rank":null,"citation_count":12,"citer_count":10,"citers_with_citation_signal":9,"citers_with_endowment":9,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":168272,"name":"Michael Fedak","orcid":null,"position":1,"is_corresponding":false},{"id":168273,"name":"Lars Boehme","orcid":null,"position":2,"is_corresponding":false},{"id":168271,"name":"Samantha Alex Gordine","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"base_score":2.4849066497880004,"endowment":2.4849066497880004,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"26486362","pmcid":"PMC4712810","openalex_id":"https://openalex.org/W2282334386","authors":[],"funders":[{"funder_name":"Natural Environment Research Council","grant_id":"NE/J005649/1","title":null},{"funder_name":"Natural Environment Research Council","grant_id":"1320585","title":null},{"funder_name":"Natural Environment Research Council","grant_id":"NE/E018289/1","title":"SAVEX South Atlantic Variability Experiment"},{"funder_name":"Natural Environment Research Council","grant_id":"smru10001","title":null},{"funder_name":"UK Research and Innovation","grant_id":"NE/L501852/1","title":"St Andrews-2013-DTG Funding 3 Studentships"}],"total_grants":5,"fwci":0.9381,"citation_percentile":0.79350351,"influential_citations":0,"citation_trend":[{"year":2017,"count":1},{"year":2018,"count":2},{"year":2019,"count":4},{"year":2021,"count":1},{"year":2023,"count":1},{"year":2024,"count":2}],"oa_status":"hybrid","license":"cc-by","oa_locations":[{"url":"https://jeb.biologists.org/content/jexbio/218/23/3816.full.pdf","host_type":"journal"},{"url":"https://jeb.biologists.org/content/jexbio/218/23/3816.full.pdf","host_type":"HYBRID"},{"url":"https://jeb.biologists.org/content/jexbio/218/23/3816.full.pdf","host_type":"publisher"},{"url":"http://journals.biologists.com/jeb/article-pdf/218/23/3816/1889636/jeb118109.pdf","host_type":"publisher"},{"url":"http://journals.biologists.com/jeb/article-pdf/doi/10.1242/jeb.118109/2033267/jeb_118109.pdf","host_type":"publisher"},{"url":"https://doi.org/10.1242/jeb.118109","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/26486362","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/4712810","host_type":"repository"},{"url":"http://www.smru.st-andrews.ac.uk/Instrumentation/Overview/","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC4712810","host_type":"Europe_PMC"},{"url":"http://dx.doi.org/10.1242/jeb.118109","host_type":""},{"url":"https://dx.doi.org/10.1242/jeb.118109","host_type":""},{"url":"https://hdl.handle.net/10023/7923","host_type":""},{"url":"https://www.scopus.com/pages/publications/84962909327","host_type":""},{"url":"https://doi.org/https://doi.org/10.1242/jeb.118109","host_type":""}],"fields_of_study":["Marine animal studies overview","Underwater Acoustics Research","Ship Hydrodynamics and Maneuverability","Medicine","Geology","Biology","Environmental Science","0106 biological sciences","0301 basic medicine","01 natural sciences","03 medical and health sciences","Animal Migration","Animals","Antarctic Regions","Body Composition","Data Interpretation, Statistical","Diving","Knowledge Bases","Seals, Earless","Telemetry"],"mesh_terms":["Animals","Antarctic Regions","Body Composition","Data Interpretation, Statistical","Diving","Telemetry","Animal Migration","Seals, Earless","Knowledge Bases"],"keywords":["Buoyancy","Neutral buoyancy","Elephant seal","Foraging","Southern elephant seal","Geology","Oceanography","Water column","Geodesy","Paleontology","Ecology","Mechanics","Computer science","Biology","Physics","Telemetry","Foraging ecology","Body condition","Body composition","Marine mammal","Diving Behaviour","Drift Diving","Seals, Earless","QH301 Biology","Diving","Knowledge Bases","590","NDAS","Antarctic Regions","QH301","Animals","SDG 14 - 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