A squirrel can be found on the ground level of this otherwise tall track.
Go through the track up until the 5th checkpoint. Jump over the gap and inch your way up to the end of the next ramp until you see the box fall over. Back off of the ramp and you'll land on another platform; bail out and fling yourself off of the side of the platform and you'll fall to the ground, where you can see a squirrel sitting on a box.
It's just a squirrel :)
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