First Paragraph
“Biologging” through temporary attachment of miniaturized data loggers on marine animals is revolutionizing the science of marine ecology (Block et al., 2011; Hussey et al., 2015). It also offers new capabilities to observe the ocean. In addition to collecting location and depth information useful for studying foraging behavior, these devices can record vertical profiles of temperature and salinity (Fedak, 2004; Costa et al., 2010), data that are used to improve knowledge of ocean state and its variability.