Suction-cup tagging research

In March 2007 we were joined by our colleagues John Calambokidis and Greg Schorr of Cascadia Research Collective of Olympia, Washington, to conduct a program of attaching suction-cup dive loggers to study the foraging and feeding behaviour of blue whales. John and Greg are acknowledged as foremost specialists in the attachment of these tags, and we developed a great working relationship with them. This work is central to Margie’s Ph.D. on blue whale foraging behaviour, and allowed us to record the feeding dives of blue whales in three dimensions, overcoming the huge limitation that we normally have: that the movements of whales are invisible to us once they dive. We were able to tag seven blue whales, including a male-female pair for the first time. The tagging data, when analysed together with Margie’s krill hydroacoustic (sonar) data and temperature and salinity at various depths, will enable us to relate blue whale foraging behaviour to their upwelling habitat and their prey, krill. Margie’s work is focusing at the fine scale of individual whale behaviour, while Pete’s work has mainly focused on the bigger picture of whale distribution and ecology across the whole feeding area.