I currently have a pair of Rosies that are nearing breeding age, and will be adding another adult female this week. I will be looking for another male, but in the meantime could I hope that the current male would breed with one female, then the other while the first is nesting ?

My experience:
In the past I had 3 Bourkes (male and 2 females) in one cage. Few first months everything was ok untill one famale started chasing other Bourkes. Then a breeding season was coming so I'm not sure if this was a reason. I hung a nest box after saperating this one female.

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Sorry for my English (I learn here )
Our current fids:
GCC: Zenek (M); vids: https://www.youtube.com/playlist?lis...RA9Tqq3oRJa6mf
Bourkes: Jaś (M), Fela (F), Rozalka (F); vids: https://www.youtube.com/playlist?lis...PMioyZWTArwLnj
Budgies: Romek (M); Angela (F)

Rest in peace:
Budgies: Limonka (F; ~January 2015), Szafirek (M; ~December 2013)

Bourkes are monogamous, meaning they will only accept 1 mate at a time
Aggression can be an issue with breeding pairs towards intruders as I have found in the past, so if you are planning to breed and are adding an extra bird I'd suggest to make sure the cage/aviary is big enough to be able to accommodate their territorial disputes

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