Aggression After Getting New Cockatiel

[For_the_birds]

Hello everyone. We recently got a new cockatiel (1F) as a companion for other cockatiel (2M). Since getting her, he has had a complete 180 in his behavior. He is completely obsessed with her, pacing around his cage when we separate them and biting us when she is around (he never did this before). When we bring her to a different room, he returns to his old sweet ways, but as soon as she is brought back in he flips his behavior all over again. Does anyone have any advice on how to navigate this (other than permanently separating them)?

 

[LaManuka]

Hello everyone. We recently got a new cockatiel (1F) as a companion for other cockatiel (2M). Since getting her, he has had a complete 180 in his behavior. He is completely obsessed with her, pacing around his cage when we separate them and biting us when she is around (he never did this before). When we bring her to a different room, he returns to his old sweet ways, but as soon as she is brought back in he flips his behavior all over again. Does anyone have any advice on how to navigate this (other than permanently separating them)?

Have you got them both in the same cage or do they each have one of their own? Unfortunately behaviour of an existing bird can't be guaranteed when introducing another, irrespective of whether they have gender or species in common. Either they will hate each other on sight, or get on well together, or sometimes love each other just a bit too much and occasionally to the extent of excluding you! I once had a male and female cockatiel pair (still have that male), and the male, Fang, would get EXTREMELY aggressive towards my hen, Twinkle, when she refused his advances, to the point where he would also attack me when I tried to separate them. I would have to cage poor Twinkle until Fang's hormonal rage wore off, and supervise them closely whenever they were out together. So hopefully you have a separate cage for your hen where she can spend a little quiet time, and with any luck your rooster may calm down a bit after he has become accustomed to her being around

 

[DonnaBudgie]

It sounds like he wants her bad, but you don't say how she is reacting to him. What's she like? Is she friendly to people? Tame?

I'm not sure if he's ever going to calm down hormonally enough to act like his friendly old self with her around. As you can see, a perfectly nice, well behaved bird can act totally different when the object of their desire is present and they're flooded with hormones. Hormonal female birds can act like this too. My female budgie Joey is so "boy crazy" I can't have a male budgie in the same room with her even when she's in her cage. She started a rapid puberty at 5 months old and laid 4 eggs at 6 months just from flirting with the boys through the cage bars!
If you want your male to act like he did before the female was introduced, I would consider rehoming the female. Mistakes like this happen and we can't predict them sometimes. Just make SURE she ends up loved and taken good care of.