Backyard Fowl Keepers

You could try addressing the behavior by adding some enrichment or distractions to keep the hens entertained. Sometimes they get loud due to boredom. Also, a more spacious setup may reduce the need for dominance displays.

It's possible that removing one hen could calm things down, but chickens often have a pecking order, so another could step up as the loud one. If you reduce the flock size, it may also affect the balance of the group.

Consider keeping your flock size the same but rearranging their living space. Giving them more space might help the hens settle down and reduce the noise. Also, having multiple hiding spots or perches could ease aggression.

In my experience, sometimes the noisy hens are just the more confident ones. If you remove her, another might take her place, but a reduction in flock size could at least reduce some of the noise and aggression.

You might want to try a temporary separation to see if the problem is really just the one hen or if the others are contributing. I've had luck with using an intro cage to observe behaviors before making any decisions.