Prey Studies and Feeding Behaviour

Suction-cup tagging

A new approach is being used to understand blue whale feeding behaviour in the Bonney Upwelling as part of Margie Morrice’s PhD. The Blue Whale Study team was joined by US blue whale researchers, John Calambokidis and Greg Schorr of Cascadia Research, in March 2007 to attach benign suction cups, complete with dive and acoustic loggers onto individual blue whales.

This project is expected to provide new insights into the underwater foraging and feeding behaviour of blue whales in this region, and how they respond to the changing distribution of their prey. One of the unique features of this research is the collection of prey data while following behind tagged whales.

Identifying undisturbed blue whale foraging and feeding behaviour, will also be intrinsically valuable information in terms of defining critical habitat, but also essential as baseline data in the context of measuring human disturbance and analysis of its effects.

Krill surveys

Krill is one of the most important sources of food for many marine predators, but remains very mysterious in terms of its distribution and life cycles. As part of Margie’s PhD, the team has been conducting vessel surveys in a fine-scale study area in the heart of the blue whale feeding ground.

These combine visual surveys of whales with hydroacoustic and net sampling of krill and temperature profiling of the ocean to look at, amongst other things, what characterises good whale food. The last of these surveys began in late March 2007.