I usually put nest boxes either back to back or side to back, it seems to give them the illusion of privacy.
I have wire shelving and they hold two boxes, Ive found that as long as the openings arent facing the same way the birds dont seem to mind. I sometimes do multi storey too.
YH gouldians in box marked 2 nest entrance on the left, no landing perch on that one it was a small branch but they keep pulling it out, and Emblema in the basket, nothing in the forward facing box.
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RH gouldian pair and four chicks in the right hand side box, nest material holder underneath is where the emblema raised their last four babies.
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nothing in any of these, the wire one is just a new addition yesterday, used be a cage for a light in reptile cage.
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The next two pics are the OB nest, three babies in there
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nothing in these nests although the ruddies have made a nest in the basket
nest boxes 008.jpg
There was eggs in the box facing right but they didnt hatch out. Basket has nest made by ruddies...again
nest boxes 009.jpg
There is also another two nest boxes in the aviary both face forward and another two baskets where the ruddies have been busy yet again, still no eggs from them though
So that means 12 boxes, 5 baskets and a new wire basket for 3 pair gouldians, one pair ruddies, one pair OB one pair Emblema.....bit of overkill maybe, but they certainly have choices.

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