Just Checking

The Barred Owl continues to visit our pond and bog each morning. I assumed that the frogs were all MIA, most likely consumed by Ms Hungry Owl. But she keeps retuning each morning, to the scene of the 'crime'. 
Then...last night I heard four loud and distinct 'plunk-splashes' as I walked by the pond. So Ms Owl knows that there remain at least four frogs still alive. By now I should know better than to 'second guess' a hungry Owl! 
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