Baffled and baffling

Recent experiences with birdfeeders have left us both baffling and baffled, and I'm not sure what the answer is but at least we're getting a little entertainment out of the deal.

For four years we've had two feeder stations in the front yard: a small forked pole holding two finch feeders and a large pole holding a complicated array of feeders, including a suet feeder, nut feeder, tray feeder, and a large hanging feeder usually full of sunflower or safflower seeds. The smaller pole with the two finch feeders is of no interest to squirrels because the holes in the feeder are too small to allow them access, but lately chipmunks have been climbing up the pole and just stuffing their little cheeks full of seeds before scampering off to hide them. Yesterday I sprayed cooking oil on the pole, though, and since then we've been watching chipmunks jump up onto the pole and then slide right back down again. Around here, watching chipmunks slide down a pole passes for cheap entertainment.

The other feeder station is posing a more mysterious problem. A squirrel baffle keeps squirrels from climbing up the pole and the tray is too high for squirrels to jump up; however, a really determined squirrel can jump down to the feeder from a nearby tree, but they often miss the tray entirely and end up falling farther than they had intended. I have not seen any squirrels on or near that feeder this spring, but something is getting up there, and whatever it is must be large and heavy enough to snap the weld on one of the bars, remove the screened bottom of the tray feeder, and totally dismantle the large sunflower seed feeder, sending it tumbling to the ground. This has happened twice so far and we are tired of it.

What is it? So far, all we've been able to determine is that it comes by night. A raccoon would be big enough to do that kind of damage, but I can't imagine how a raccoon could climb up the pole, and I don't know whether a raccoon would make that difficult leap from the tree.

How do you baffle a creature big and smart enough to take apart a birdfeeder station that has proudly baffled squirrels and chipmunks for four years? Frankly, I'm baffled.