Funny! I know cause I witness it too.
I've had one for 2 years,and he still jumps when it makes that noise, I crack up everytime, he's not afraid to drink out of it, but he did the same thing at first, there are times he walks by and it makes the noise and he really looses it, barking at it..
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Rhonda, Bailey, Josie and my angel Bella Rue'
"Until one has loved an animal, a part of one's soul remains unawakened."
~Anatole France~