Satellite and High-Spatio-Temporal Resolution Data Collected by Southern Elephant Seals Allow an Unprecedented 3D View of the Argentine Continental Shelf

• Published in: Remote Sensing
• Main Authors: Martinez, Melina, M, Ruiz-Etcheverry, Laura, A, Saraceno, Martin, Gros-Martial, Anatole, Campagna, Julieta, Picard, Baptiste, Guinet, Christophe
• Other Authors: Universidad de Buenos Aires Buenos Aires (UBA), 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), École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom Paris (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom Paris (IMT)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: elephant seal; Mirounga leonina; Península Valdés (PV); Argentina; seasonal front in the north of PV; water masses; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography; [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology; Argentine; Elephant Seal; Elephant Seals; Southern Elephant Seals
• Online Access: https://hal.science/hal-04328806; https://hal.science/hal-04328806/document; https://hal.science/hal-04328806/file/MRS15_2023.pdf; https://doi.org/10.3390/rs15235604

International audience High spatial and temporal resolution hydrographic data collected by Southern Elephant Seals (Mirounga leonina, SESs) and satellite remote sensing data allow a detailed oceanographic description of the Argentine Continental Shelf (ACS). In-situ data were obtained from the CTD (Conductivity, Temperature, and Depth), accelerometer, and hydrophone sensors attached to five SESs that crossed the ACS between the 17th and 31st of October 2019. The analysis of the temperature (T) and salinity (S) along the trajectories allowed us to identify two different regions: north and south of 42°S. Satellite Sea Surface Temperature (SST) data suggests that north of 42°S, warm waters are coming from the San Matias Gulf (SMG). The high spatio-temporal resolution of the in-situ data shows regions with intense gradients along the T and S sections that were associated with a seasonal front that develops north of Península Valdés in winter due to the entrance of cold and fresh water to the SMG. The speed of the SESs is correlated with tidal currents in the coastal portion of the northern region, which is in good agreement with the macrotidal regime observed. A large number of Prey Catch Attempts (PCA), a measure obtained from the accelerometer sensor, indicates that SESs also feed in this region, contradicting suggestions from previous works. The analysis of wind intensity estimated from acoustic sensors allowed us to rule out the local wind as the cause of fast thermocline breakups observed along the SESs trajectories. Finally, we show that the maximum depth reached by the elephant seals can be used to detect errors in the bathymetry charts.