I have been letting the budgies out more. They are probably out a third of the time that the tiels are out over a week. When the budgies come out, everyone gets into a party mood, and there's about a half hour of lots of activity and noise.

I was just watching Piper (male budgie) and Silver (male cockatiel) play a game of tag on top of the big cage. Silver would chase Piper, Piper would fly off, Piper would land at the opposite end of the cage, and Silver would chase him again. They did quite a few rounds of the game.

Then, all of a sudden Piper was a couple of inches from Silver, his head feathers all puffed up, talking to him a mile a minute, with lots of head bobs. Then, Silver chased Piper like in the beginning a couple of more times.

Right now, all four are in the big cage (door open) having a rest.