KJ> But with my cockatiels, the bond seems to be stronger, and I have
  KJ> never been able to split up pairs and re-pair the birds with other
  KJ> mates. Go figure.
I've certainly not had a representative sampling of cockatiels.  I've had one 
cock, and two hens.  In both cases, he seems to be much more "paired" to her 
than she is to him.  For example, I can take her out of the room, and he 
screams the "I've lost my mate" scream, while she looks at her surroundings.  
They mate on occasion, and have laid infertile eggs, which they both sat on 
like champs.
The last hen and he were a little more bonded; she would at least respond to 
his "I've lost my mate" screams, but would never initiate them.  On the other 
hand, when I took her into the vet alone, she flirted with the male cockatiel 
who was kept in the vet's office.
--- MacWoof 1.5.3
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