I took care of a hooded crow baby, who was thrown out of the nest. This one looked completely healthy, when I found it, just very malnourished with lots of white feathers and poor plumage. However, one year later the plumage has still not improved. The feathers grow, but break off and bleed very easily, and do not appear strong and healthy. It almost seems like they do not want to grow properly in the skin, so they just loosen and never become long and solid. Do you know what this can come from?
There are several known causes for leucism or white feathers in birds, some of them are related primarily or secondary to genetic problems, others are caused by deficiencies or low levels of agricultural poisoning. In this context you may find this blog post interesting.
In severe cases of deficiencies causing plumage problems, one year in captivity, meaning one complete annual moult, may not be enough to rectify the plumage problem. It is not that unusual that some birds may need two or even three years to grow a pristine plumage. In rare cases, the plumage problem will remain a permanent issue, and the bird will not be releasable.
If the feathers concerned are primaries, and they continue to break before they are even fully grown, then it might be a good idea to find an experienced corvid friendly veterinary surgeon, as it might be necessary to pull all primary feathers of the affected wing at once (forced moult). This has to be done under GA and is therefore not without risks. It is painful afterwards and the bird will therefore need pain relief and antibiotics. This should only be done by an experienced vet! The idea is that all primary feathers regrow together in a synchronised way, and will support each other, which will hopefully result into a normal plumage. If only one or two primaries are prone to break, then the required support is missing, and the feathers grow at different speeds and angles, and are prone to break early.
The aviary should also be adapted by providing a soft wood bark bedding to minimise the injury risk. Again, there is no guarantee, but it might be what is needed to get the plumage back in order.
In addition it is recommended to provide the right supplements to aid a healthy plumage development. The best product we have found is called Feather Up ©.
Last but not least, the bird should also be encouraged to bath and preen regularly. You may want to add once a week natural apple cider vinegar to the bird bath, as this will help to keep the water fresh and is good for the plumage (0.5% ACV or 5ml per litre).