There are a number of reasons birds get blood feathers.
Sometimes they fall during a night fright.
Blood feathers can be broken in a flight accident, when your bird is preening or just frightened and flapping about.
When clipping flight feathers to restrict flying be sure not to cut feathers so short that they don’t offer the right amount of protection for new feathers that are just coming in.
What happens is the short trimmed feathers break on impact because the longer primary flight feathers (which are now cut) are not there to take the brunt of the impact.
Answer to what are these blood feathers was added 03/06/2018
I recently had the mobile bird trimmer come to the house and she found that my Mealy Amazon (22 yrs) and one of my Pionus (10yrs) had these at the base of what was, or was to be a feather.
What are they, what is causing them? Lack in diet?
Those are emerging blood feathers. They are not fully matured blood feathers. Normally feather barbs on a bird are attached to empty shaft with no blood once they are fully mature.
That is why you can trim a bird’s wing with no pain much like cutting in here or fingernails.
During a molt as feathers are lost new ones come in and blood is used to supply the growth of the.
Important to watch broken blood feathers as they can cause serious bleeding which birds in general don’t do well with.
Your mobile crew compared to do the right thing by pulling these out to avoid the bleeding.
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