Ocean temperature measured by elephant seal-CTDs in the Southern Ocean with links to datasets ...

• Main Authors: McIntyre, Trevor, Ansorge, Isabelle J, Bornemann, Horst, Plötz, Joachim, Tosh, Cheryl Ann, Bester, Marthán Nieuwoudt
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2011
• Subjects: Marine endotherm; MAR2004; MAR2005; MAR2006; MAR2007; MAR2008; Marion Island Research Station; Marine Mammal Tracking MMT; Southern Ocean; Elephant Seal; Elephant Seals; Marion Island; Southern Elephant Seals
• Online Access: https://dx.doi.org/10.1594/pangaea.793267; https://doi.pangaea.de/10.1594/PANGAEA.793267

The potential effects of ocean warming on marine predators are largely unknown, though the impact on the distribution of prey in vertical space may have far reaching impacts on diving predators such as southern elephant seals. We used data from satellite-tracked southern elephant seals from Marion Island to investigate the relationship between their dive characteristics (dive depths, dive durations and time-at-depth index values) and environmental variables (temperature at depth, depth of maximum temperature below 100 m, frontal zone and bathymetry) as well as other demographic and behavioural variables (migration stage, age-class, track day and vertical diel strategy). While other variables, such as bathymetry and vertical diel strategy also influenced dive depth, our results consistently indicated a significant influence of temperature at depth on dive depths. This relationship was positive for all groups of animals, indicating that seals dived to deeper depths when foraging in warmer waters. Female seals ...