Marc Oremus of the University of Auckland and Scott Baker, associate director of the Marine Mammal Institute at Oregon State University, and colleagues published a genetic study of pilot whale mass strandings in Australia and New Zealand in the March 14, 2013, issue of the Journal of Heredity that challenges all present theories about the cause of mass pilot whale strandings.
The genetic analysis of 490 individual pilot whales from 12 different stranding events found no direct correlation between mothers and young calves. Mothers and calves could be identified as being related in some instances but their bodies came ashore at large distances from each other. In the majority of instances the scientists observed there was no genetic relationship between female, male, or baby whales involved in strandings.
This research opposes the presently held theory that mother and baby pilot whales strand together due to a maternal bond displayed in most whales. The research also negates the commonly held conception that pilot whales are motivated to strand in large groups as a care giving behavior.
The researchers state that they really do not know what causes mass pilot whale strandings but they recognize some social interaction as being a factor in the phenomenon that has been recorded for over 2,000 years.