Hi,
Do you know what sex the other three are? If not, then you could have 4 females. Have you seen any of the birds mate with the one that laid eggs? I think the best thing to do is remove the nest box and discard the eggs. Unless you can tell that there is a male that is bonded with her, and have seen them mate, then most likely the eggs aren’t even fertile. If there was a bonded pair, it is highly unlikely that they would allow two other birds in the nest box. Breeding birds are typically very territorial and aggressive, even with flockmates. Also, is there a chance that these birds are related? Maybe they are all siblings, and you definitely can’t allow breeding of related birds. Again, taking the nest box away and discarding the eggs will be the best solution. Even if the eggs are fertile, it takes at least 48 hours of incubating the eggs around the clock for the egg to start any growth. And you don’t want these eggs to hatch if these birds are related. If these are green cheek conures, they are already getting very inbred due to indiscriminate breeding. I would let them remain a non-breeding flock, which means no nests, bird tents or huts or anything they can get inside of. Breeding just tends to set off territorial battles and birds get hurt or killed.
Thank you for asking Lafeber,
Brenda