There is a lot going on in your post. A lot of it has been addressed but I'll give my take. I don't think you have much to worry about.
As some said, an egg eater is a chicken that purposely opens an egg to eat it. About any chicken will eat an egg that is broken, that's pretty normal. It sounds like an egg was accidentally broken. How? Who knows. It could have been scratched out of the nest, maybe when a hen was rearranging the nest to lay. Maybe it was broken in the nest and one carried half the shell out of the nest. I had two broody hens fight over some eggs one time, all the broken eggs stayed in the nest. Maybe something else.
I had an egg-eating hen once. When she opened an egg in the nest not all the shell was cleaned up and a soggy mess was left in the nest. If a hen is opening eggs consistently you should see signs occasionally. I think what caused her to open eggs to eat was a pullet was laying form the roost an egg broke. But that is just a guess.
A lot of hens do not sing the egg song, that is totally normal.
It is pretty common for me to see two or even three hens crowded into one nest laying with the other nests open. Most hens seem willing to share. But I've also seen a dominant hen grab a pullet by the head and jerk her out of the nest so she could lay there in private. That same hen might be willing to share a nest with older hens, just not that pullet. I had a nest hog that would stay on a nest for three hours laying her egg and would not let another hen share. I keep a fake egg (I use golf balls but ceramic or wooden eggs or plastic Easter eggs can work) in each nest. They do have a favorite nest, which can vary day to day or week to week but i usually get a majority in one nest with a few in the others. What i'm trying to say is that they are not all that consistent about this. Each has its own personality and about anything can happen. If you want to try to spread them out try putting a fake egg in every nest except the popular one. See what happens. It may work, it may not.
I don't know what caused that commotion. My set-up is a lot different from yours and I raise a lot of cockerels with the flock. When they fight it's usually not that loud but i have loads of room. As tight as yours are in that tractor maybe the proximity of a fight caused it. Chickens have a lot of different vocalizations, they do communicate. One time I had a snake in the coop. The chickens were all gathered outside and making sort of a whining sound, it was not that loud. When they are scared but seem to not know for sure what is going on mine might all get worked up with a sound pretty close to the egg song. That really gets loud. My guess is that one of them saw something that made her nervous, maybe a predator but maybe something else, and started that sound. The others joined in. I scared mine once when I carried a small camera down there, they were not used to the camera.
You get a lot of different opinions on feeding them extra calcium. If Layer is all they are eating they should get enough calcium for the egg shells. Should but some hens have different efficiencies on their digestive track. But yours are in a tractor, they are probably foraging some low calcium feed. You may be giving them low calcium treats. If you live in limestone country they may be getting a lot of calcium from the rocks they eat. They can pick up some calcium from certain plants they eat or even some creepy crawlies they may catch. A fair portion of the calcium they eat from oyster shells, egg shells, Layer feed, or anything else is never digested but travels on through the system and out the back end. Let your egg shells tell you how you are doing with the calcium. If the egg shells are hard enough you are doing OK. If they are soft or thin you may need to do something different. Some people like to tell you what is best, but they could be in different circumstances. In my opinion if what you are doing is working, it is working. You are doing well enough.
I probably missed something but that's enough this morning. Hopefully this will help you determine if you do have a problem. Good luck!
As some said, an egg eater is a chicken that purposely opens an egg to eat it. About any chicken will eat an egg that is broken, that's pretty normal. It sounds like an egg was accidentally broken. How? Who knows. It could have been scratched out of the nest, maybe when a hen was rearranging the nest to lay. Maybe it was broken in the nest and one carried half the shell out of the nest. I had two broody hens fight over some eggs one time, all the broken eggs stayed in the nest. Maybe something else.
I had an egg-eating hen once. When she opened an egg in the nest not all the shell was cleaned up and a soggy mess was left in the nest. If a hen is opening eggs consistently you should see signs occasionally. I think what caused her to open eggs to eat was a pullet was laying form the roost an egg broke. But that is just a guess.
A lot of hens do not sing the egg song, that is totally normal.
It is pretty common for me to see two or even three hens crowded into one nest laying with the other nests open. Most hens seem willing to share. But I've also seen a dominant hen grab a pullet by the head and jerk her out of the nest so she could lay there in private. That same hen might be willing to share a nest with older hens, just not that pullet. I had a nest hog that would stay on a nest for three hours laying her egg and would not let another hen share. I keep a fake egg (I use golf balls but ceramic or wooden eggs or plastic Easter eggs can work) in each nest. They do have a favorite nest, which can vary day to day or week to week but i usually get a majority in one nest with a few in the others. What i'm trying to say is that they are not all that consistent about this. Each has its own personality and about anything can happen. If you want to try to spread them out try putting a fake egg in every nest except the popular one. See what happens. It may work, it may not.
I don't know what caused that commotion. My set-up is a lot different from yours and I raise a lot of cockerels with the flock. When they fight it's usually not that loud but i have loads of room. As tight as yours are in that tractor maybe the proximity of a fight caused it. Chickens have a lot of different vocalizations, they do communicate. One time I had a snake in the coop. The chickens were all gathered outside and making sort of a whining sound, it was not that loud. When they are scared but seem to not know for sure what is going on mine might all get worked up with a sound pretty close to the egg song. That really gets loud. My guess is that one of them saw something that made her nervous, maybe a predator but maybe something else, and started that sound. The others joined in. I scared mine once when I carried a small camera down there, they were not used to the camera.
You get a lot of different opinions on feeding them extra calcium. If Layer is all they are eating they should get enough calcium for the egg shells. Should but some hens have different efficiencies on their digestive track. But yours are in a tractor, they are probably foraging some low calcium feed. You may be giving them low calcium treats. If you live in limestone country they may be getting a lot of calcium from the rocks they eat. They can pick up some calcium from certain plants they eat or even some creepy crawlies they may catch. A fair portion of the calcium they eat from oyster shells, egg shells, Layer feed, or anything else is never digested but travels on through the system and out the back end. Let your egg shells tell you how you are doing with the calcium. If the egg shells are hard enough you are doing OK. If they are soft or thin you may need to do something different. Some people like to tell you what is best, but they could be in different circumstances. In my opinion if what you are doing is working, it is working. You are doing well enough.
I probably missed something but that's enough this morning. Hopefully this will help you determine if you do have a problem. Good luck!
