What are blood feathers?
Blood feathers, also called "pin feathers," are new feathers that are starting to grow. Since they are actively growing, they need a large blood supply and will bleed if broken, hence the name. Each blood feather grows from a special area in the skin called a follicle. The feather has an artery and vein that extend up into it from the follicle and nourish the feather. Due to the color of the blood supply, the shaft of a blood feather will appear dark, whereas the shaft of an older feather will be white. A blood feather has a larger quill (calamus) than a mature feather. A blood feather starts out with a waxy keratin sheath that protects it while it grows. When the feather is mature, the blood supply will recede and the waxy sheath will be removed by the bird.
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