I bet you had fun watching her try to open the container. It's probably a great enrichment item that really gets her thinking. You always seem to have good luck catching the animals doing interesting things.
They are not showing well but there are holes for the echidna to put that short-beak thru to get the treats in the container.
I heard that this set-up was because the wallabies (or maybe it was the wombats) really like echidna food and they want to ensure that only she can eat it.
Well that sounds like a pretty interesting way to make sure she gets to eat. Wonder who had that idea. This is why keepers deserve a ton of credit they come up with some really interesting solutions to equally interesting problems.
