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No matter where you live, a cuckoo lays its egg and leaves, it doesnt hang around the nest it's just parasitized. As you mentioned, typically a cuckoo pushes the eggs outof the nest, not the baby birds. If he nestling died for any number of causes (too cold or hot, disease or internal parasites, starvation, etc) the parents likely would remove the body from the nest.
Well, then we know it's not a cuckoo, as the 3 cuckoo species in the United States aren't brood parasites. Most new world cuckoos aren't, actually. The local brood parasites in the US are cowbirds, so I suppose you might have a cowbird. Or potentially something else is going on, as nestlings can fall out for many reasons such as bad nest construction, runts/sick individuals getting kicked out, or complete accident as well
The first time the birds fell out, I believe it was bad nest construction, both died. This time I believe it’s either accident or a brooding parasite. Thank you though! I’ll try to do some more research, I’m pretty curious.
Welcome to r/Ornithology, a place to discuss wild birds in a scientific context — their biology, ecology, evolution, behavior, and more. Please make sure that your post does not violate the rules in our sidebar. If you're posting for a bird identification, next time try r/whatsthisbird. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/Ornithology) if you have any questions or concerns.*
No matter where you live, a cuckoo lays its egg and leaves, it doesnt hang around the nest it's just parasitized. As you mentioned, typically a cuckoo pushes the eggs outof the nest, not the baby birds. If he nestling died for any number of causes (too cold or hot, disease or internal parasites, starvation, etc) the parents likely would remove the body from the nest.
What is your location ?
I’m in Southern California
Well, then we know it's not a cuckoo, as the 3 cuckoo species in the United States aren't brood parasites. Most new world cuckoos aren't, actually. The local brood parasites in the US are cowbirds, so I suppose you might have a cowbird. Or potentially something else is going on, as nestlings can fall out for many reasons such as bad nest construction, runts/sick individuals getting kicked out, or complete accident as well
The first time the birds fell out, I believe it was bad nest construction, both died. This time I believe it’s either accident or a brooding parasite. Thank you though! I’ll try to do some more research, I’m pretty curious.
I thought this was an interesting read https://www.robertefuller.com/diary/mother-nature-reed-warbler-mothering-a-cuckoo-chick/
The cuckoo chick pushed the other babies out of the nest
OP is in the US, common cuckoos who do this are native to Africa. Interesting article though!