ABSTRACT
White Sharks from New Zealand typically make long-distance migrations across open ocean to tropical locations in the southwest Paci¢c Ocean, resulting in major changes in habitat type and temperature regime. This study explored how White Sharks use the vertical dimension of their habitat, and the thermal environment they encounter. Between 2005 and 2009, 25 sharks were tagged with pop-up satellite tags around New Zealand. Twenty of the tags reported useful data, including four that were recovered, thus providing high-resolution archival information on depth and temperature. We analyzed depth-related behavior patterns in the vicinity of New Zealand seal colonies (shelf phase) and while crossing open oceans (ocean phase) to tropical regions (tropics phase). The sharks exhibited major changes in behavior among phases. They mostly stayed in shallow water less than 50 m deep in temperatures of 10-16°C during the shelf phase but had a bimodal depth distribution in the ocean phase, switching between surface swimming and diving to 200-800 m.
