How do blue whales kill their prey?

Blue whales eat krill, which are crustaceans like shrimp, but almost microscopically small. They take them into their mouths with water, and filter them out of the water with baleen plates. Baleen is a material rather like horn, which is arranged in many narrow strips like teeth in a comb, and used as a sieve. A blue whale can eat 40,000,000 krill in one day.
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