The current issue of Live Science includes a fascinating article by staff writer Tia Ghose on a killer whale study that indicates some pods of killer whales or orcas hunt only fish, primarily salmon, while others hunt exclusively seals, walruses, sea lions and whales. The mammal-hunters do not intermix or interbreed with the fish-hunters, the scientists say. And the mammal-hunters have learned to “go dark”: they hunt in silence, listening for their prey to surface and breath–read the whole story at http://www.livescience.com/41671-killer-whales-hunt-in-darkness.html?cmpid=556084
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