i don't know much..but
i don't think there is much way to prevent this you can't keep birds away from eachother for 1 or 2 just cause they might hirt innocent Jazz. from what i hear it is almost a chance you take!
it's like any animal the dogs (if you got 2)new to eachother might fight till blood....it's any animals instinct, how male Crocodiles,Birds,Giraffes,Lions,Gorilla's and more, all fight for the female...you can't prevent that unless you take them away from eachother for a while, which is kinda hard for bouncy Baby's who want to roam the House!
if anybody thought i said it wrong please correct me..it's hard to get whats on my mind!
JMD