Help needed pecking order fighting

Hi I have two call ducks one male and one female and one red hen as the other died in November the three have lived together fine since November, after a bit of research and talking with a breeder we decided to get another hen to go with our existing red , on tues we went to collect our amber Link who is 17 weeks old, there has been some quiet heavy pecking fighting between the red hen and call duck against the newbie I'm aware they will be finding the pecking order again, this is the first time I have introduced any New hens ,and the noise when it happens sounds like mass murder in the the back garden, the amber link has found refuge on top of the coup during the day which causes no harm to anyone she is eating fine as I fed her up there yesterday and actually in the coup last night when the others were out and about ,will this calm down in the next week or so or will I have to look into building a coup for her on her own just bit worried she may get injured as when she is being pecked on she buries her head down and trys to hide , thanks for your help

Hi thanks for that just been out to check on her she is fine and eating well I let the old hen get her perch first then place the new one in on a spare one once gets dark am I doing the right thing or should I just let her find her own space, we may have room for one more so may have a trip down were we got her from on sat.

I agree with the advice you have been given by New Shoot and ANHBUC.  Unless you really don't have room, a companion for your new hen would be a very good idea.  Red Hen will almost certainly stay in charge but she's much less likely to do more than the occasional peck to remind everyone she's number 1 if there are two others (as well as the ducks), and the two can be newbies together.  My top hen is a very dominant Blackrock who since she has had a flock of four others "under" her -a Welsummer and three RIRs one of which is a bantam- has become a most gracious leader!