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Michael Fishbach and his friends were in the Sea of Cortez on Valentine's Day this year when they found a humpback whale floating in the water. It appeared to be dead, having been trapped in a fishing net for a long time. Fishbach discovered that she was still alive -- but only barely. They worked hard for an hour with only one knife to cut the net away and free her. They were ultimately successful. Skip ahead to 6:20 to see the whale's joyful reaction.
-via Nag on the Lake