ok so, I did look up on this but nothing works!!! they have enough spaced plenty of grass and are healthy! I am scared one well end up getting an infection from how bad its getting. the bite marks are horrible!!! they do it like everyday and when I remove the bully she just became so depressed and it didn't help because the others started doing it. one got so bad I had to remove her and put some med spray so the wound wouldn't get infected. now today I put her back with her sisters but it just turned into a huge mess!! blood everywhere... every duck was bleeding horrifically! I do spray them so they don't get infected and I am going to my local chicken and duck breeder to ask them because that is where I get all my ducks. just need a second opinion.. thanks!