Today is indeed a better day for the Stafford who was attacked yesterday. The bird's expression looks like a smile to me!
Even 24 hours and this bird is making remarkable improvement and its condition has been upgraded.
Some general suggestions for preventing attacks:
1. Separate male and female chicks as soon as possible and keep them separate until both are in full breeding condition and ready to mate and raise their family. Checking to see the male feed the hen through the wire or seeing the hen assume a mating position when she hears a male sing the breeding song are signs that they are ready for pairing. If one of the two is not ready, a fight will surely break-out.
2. Separate crested and non-crested birds. The small bare spot in the center of the crest is irresistible to a non-crested bird. If a bird has been picked or if any blood is showing like from a broken young feather, separate it from all other birds.
3. Limit the amount of protein in the diet until birds are actually feeding babies. Animal protein in particular causes aggression.
Sudden change in the amount of protein in the diet can also cause problems. Vegetable protein is a better conditioner for breeding than animal protein.
4. When grouping birds, avoid overcrowding and introduce all of the new grouping to the cage at the same time. Adding a bird to a group will change the dynamics and can result in territorial fighting with someone getting hurt, often the new guy on the block is picked on.
So what do I think happen in this case, well remember last week when I ran out of seed and made my own mix because the roads were too slick to go get it, I think although it was a good nutritious mix, it was too much of a protein change for this group of four birds. (I left the Staffords on it a few days to clean up what I had made.)
I am checking the other three birds carefully daily and I have them back on L'Avian Plus seed and I have not seen any more problems.