Well, when a mommy bird and a daddy bird love each other very much…
Seriously, after the first hatch, which could catch someone by surprise, the rest are the human’s choice. Separate the sexes if you don’t want to be a bird mill, or easier yet, replace the fertile eggs in the nest.
In general, pet stores remove any stray eggs before the public sees them. When I was involved in 4H as a child, all sorts of fowl (including ducks and geese) laid eggs in their small display cages while awaiting the judges, and the (human) competitors nervously monitored their birds and tried to remove the eggs (I’m not sure why, but it was considered bad form – maybe evidence of neglect? – if there was an egg in the cage when the judges came by). So that’s an example of humans deliberately removing the eggs so that people don’t see them.
All to familiar with this issue! In our case, her cere (that patch of skin above the beak) turned blue then deep purple then abruptly pale tan just before she laid the egg and disabused us of the notion she was a boy. In other words, the color wasn’t wrong at the time she laid, but it was a moving target throughout her adolescence.
My cousin’s cockatiel, Frosty, layed at least five eggs this spring (unfertilized.) Every time my cousin took one away from her, there would be another in a few days.
We used to get fresh eggs from farmers in at our grocery store. Mother always broke each egg into a cup before putting it into a skillet because every now and then she would break one that had a half developed baby chick in it. That is just no way to start the day.
Then we got five hundred plus baby chicks that grew into adults. The roosters were aufed and the hens were put in cages. I gathered the eggs. Let me tell you, they don’t come all fresh and pretty.
One time there was a hen that laid one about the size of a goose egg. I just felt so miserable for that poor hen.
I now prefer to buy free ranch eggs to atone for the sins of my fathers.
I saw some “grade Z” chicken eggs at a 4-H exhibit at the fair this year. They looked very strange - all jacked up, they were! So the eggs do not all come out smooth and pretty.
It was lovebirds that my neighbor had, breeding away in their cage.
As others have said, they do. My friend used to have several cockatiels (I believe; they might have been something else) and they’d frequently lay eggs. None were ever fertilized, though, so she never had any baby birds (though early on before she got used to the behavior, she’d hoped she would).
All these responses and no one’s admitted to eating one of these eggs? Come on! This is the message board that invented pan-fried semen! Where’s your sense of adventure? (And wouldn’t parrot eggs have been the perfect meal to prepare on Talk Like a Pirate Day?)
My lovebird laid twenty eggs in a two-week period, but despite both parents brooding them, none of them hatched. I have a pair of cockatiels that hatched out a clutch last Super Bowl, gorgeous lemon yellow things they were!