+1
Squirrels. We have a bird feeder we thought was out of their reach, but they managed to find a way to climb on it and shake it so the seed falls all over the deck.
We built a squirrel feeder for them last year with a door they can open so they can take out the sweet, sweet peanuts inside. Not only did they eat all of them within minutes, they not only moved the little glass window in front of the peanuts after we refilled it again so that they all spilled out on the ground, but they also confiscated the window, this rendering the feeder useless.
They are insatiable and relentless.