This caused a bit of a panic the first time I saw it happen. There is a seed block hanging outside one of our windows. A surprising variety of birds visit the seed block, including mockingbirds and brown thrashers. It was a fairly new addition to our collection of bird feeders. I happened to look out the window, and something looked a little off.
The chickadee was inside the cage holding the seed block. I was a bit worried about something like this having read stories about chickadees getting themselves into places such as the inside of tube feeders. So now the question was, did we need to let it out? We watched for a bit, and eventually the problem resolved itself without issue. The holes in the cage are large enough for a chickadee to get in and out without trouble. I don’t know if it makes it easier to get to a chosen seed, or if there is some other logic behind it. Once I saw two in there at once, but that didn’t last long. Another time, one squeezed itself in on top of a fresh seed block. This is a frequent sight whenever the chickadee thinks he will fit.
If you are curious it is a Pennington Premium seed block.