Caique sleeps on back

[stevenkotlarz@att.net]

I've been noticing that my Caique has been sleeping on its back, in its food bowl looking like a dead bird. The first few times I ran to the cage freaking out and she just jumped up and starting playing like she usually does. I asked my vet about it and he basically said caiques are strange birds and I should provide a softer sleeping spot, lol, so I got her one of those little nest looking things so now she sleeps there on her back. My question is has anyone else seen this in any species, I haven't really heard of this much and I certainly have never seen it unless we were about to have a birdy funeral.