I saw this the last time I was out with the chickens. This is just another example of Piper's... stupidity? That sounds so mean... Let's just say confused curiosity.
This is when Piper notices the bucket.
Note that Raven is in this picture but not the next. She realized in that time that buckets are not interesting.
Piper has a very different opinion.
She looks closely at the bottom of the bucket.
Then she looks at the top of the bucket.
Then the bottom of the bucket... again...
And the top again... In case it changed? I guess you never know...
What a sweet, silly chicken!