Cockatiels and budgies in one aviary

Mixing cockatiels and budgies in a shared aviary is one of those setups that can absolutely work, but it needs to be done thoughtfully — cockatiels are bigger and can inadvertently injure budgies, especially during squabbles over perches or food, and budgies can be surprisingly feisty and nippy toward tiels. Bird welfare needs vary a lot by species, and the two most underestimated factors are almost always cage size and social dynamics. Before I give you a proper steer, can you tell me a bit more? What kind of space are you working with — indoors or outdoors — and have any of these five birds lived together before, or is this a new arrangement you're planning?

That's actually a reasonably good starting position. They've had visual and auditory exposure without the stress of sharing territory, which tends to make introductions smoother. The fact that your tiels are an established group and your budgies are a bonded pair means you've got two settled social units — that's easier to work with than a random mix. The key risks to manage are: tiels accidentally standing on or biting budgies (usually not aggression, just clumsiness or mild dominance), competition at food and water stations, and budgies harassing tiels during breeding condition. Can I ask — are any of them in breeding condition, or do any show nesting behaviour currently?

Good — no nesting boxes is the right call for a mixed aviary, it removes a major trigger for aggression. For five birds sharing a space, the single most important thing is size. You need something large enough that each species can establish its own zones — tiels tend to favour higher perches, budgies are more active and mid-level. I'd recommend the Prevue Hendryx F040 Flight Cage. It's 37 inches wide by 24 deep by 60 tall, which gives genuine flight space rather than just standing room, has multiple doors for easy feeding and access, and the bar spacing at half an inch is safe for both species. It's well built, holds up to indoor aviary use, and is available on Amazon UK. Set it up with perches at two distinct height levels, and run at least three feeding stations to reduce competition at the bowl.

Gradual is always better with mixed species. Set up the new cage completely fresh — no bird has prior ownership of it, which levels the playing field. Put everyone in at the same time rather than introducing one group to the other's established territory. For the first week, watch feeding behaviour closely: if the tiels are monopolising food stations or if the budgies are persistently chasing the tiels, add more stations immediately. Also keep the previous cages accessible for at least two weeks so you can separate anyone who's struggling without a scramble. Most mixed cockatiel-budgie groups settle within two to three weeks if the space is adequate.

You're well set up for this — established groups, no active breeding behaviour, and you're thinking it through properly rather than just throwing them together. The Prevue F040 is a solid choice for five birds of those two species. If you do hit persistent aggression after a few weeks once they've settled, it's usually a space or resource issue rather than species incompatibility, and it's almost always fixable by adding perch options or feeding points before resorting to separation. Good luck with them.