A flock sorts out small disputes with a peck and a step back, and that ordinary ordering is not the concern here. Relentless pecking is different: several birds, or one determined bird, returning to the same victim, pulling feathers, and breaking skin. That pattern means something in the flock's conditions or the victim's health needs attention, and it needs it promptly.
Intervene First: Separate a Bleeding Bird
If blood has been drawn, take the victim out. Blood on feathers attracts more pecking, and a wound that starts small can deepen fast when the flock keeps working at it. Move the injured bird to a clean, quiet pen or crate within sight of the flock if possible, with her own food and water, warmth in cold weather, and a safe place to rest without being reached through wire.
Clean a wound gently, watch for flies in warm weather, and contact a vet if a wound is deep, keeps bleeding, or the bird stops eating or seems dull, because flock pecking can injure far more seriously than the feathers suggest. A pecked bird returns to the flock only when she is fully healed, with no open skin or scab the others can target, and ideally at a calm time with extra feed points set out and someone watching the first hour, ready to separate her again if the attack restarts.
Read the Flock: Space, Feed Points, and Boredom
With the victim safe, look hard at the conditions that built the pressure. Overcrowding is a leading possibility: too many birds in a run, perches packed at night, and no ground where a low-ranking bird can simply get out of the way. Feed and water points matter just as much, because one feeder guarded by confident birds starves a timid bird into weakness, and a weak bird invites more pecking. Add stations, spread them apart, and make sure every bird can eat without crossing the whole flock.
Boredom pushes pecking too, especially in a bare run during long days indoors. Scatter grain to work through, hang greens to pull at, add dust-bathing ground, perches, and objects that change the space, and give the flock room to forage if you can. Consider the victim herself as well: a bird who is ill, molting heavily, or moving stiffly can draw attacks, and illness as a cause means she needs checking in her own right, not only protection from the others.
Flock Watch Until the Pattern Changes
Intervening once rarely settles it. Assign a flock watch for the following days: who checks at feeding, who looks for new feather loss or a bird hiding from the flock, who cares for the separated bird, and who notes whether one aggressor is starting each attack. If a single persistent aggressor keeps going after every fix, separating that bird for a stretch can reset the flock's habits while the victim recovers among calmer company.
Time reintroductions with the same care as the separation. Bring the healed bird back when the flock is calm and feeding, add an extra feed station for the first days, and stay to watch rather than releasing her and leaving, because the first hour tells you whether the old pattern is restarting. Some keepers reintroduce at roosting time, when birds are settling for the night, and then watch the morning closely, since breakfast competition is where old rankings get tested. If pecking restarts at the healed spot, separate her again and give the flock more time and more space work rather than hoping a second round resolves itself.
Write those observations down with the bird described clearly, because 'the speckled hen, left side' prevents the wrong bird being caught and the right one being missed. That written watch is what KinsLe holds well, as the Care Teams list keeps separation care and daily flock checks assigned until the victim is safely back.