Behavior brief

Orcas splash to kill

Orcas hunting in a group Image: Wikimedia commons, Wolfgang Hagele

When killer whales splash around in the water, it's not all for fun and games. linkurl:Research;http://onlinelibrary.wiley.com/doi/10.1111/j.1748-7692.2010.00453.x/abstract in Marine Mammal Science describes a hunting behavior in one group of orcas, dubbed "pack ice killer whales," in which the whales swim as a group toward a seal lying on a chunk of ice, pumping their tails in unison to create waves that wash the resting seal into the water where they can kill and eat it. While this behavior, first described in 1981, has been observed occasionally in the last 30 years, the current study describes 22 instances of wave-washing hunting in just 75 hours of observation, suggesting the technique may be more widespread than previously suspected. (Hat tip to linkurl:ScienceNOW;http://news.sciencemag.org/sciencenow/2011/04/slideshow-killer-whales-devise-l.html )Oxidative stress influences greenfinch personalitiesThough some remain skeptical of the idea of animal personalities,...