What does the term "blood feathers" indicate?

The term "blood feathers" refers to feathers that are still in the process of growth and contain blood. During feather development, particularly when a bird is molting or growing new feathers, the shaft of these feathers is filled with blood vessels that nourish the growth of the feather. This makes them vulnerable; if a blood feather is damaged, it can result in significant bleeding and even lead to serious injury for the bird.

Understanding this concept is crucial for falconers and bird handlers, as they need to be able to identify blood feathers in order to handle birds safely during training or care, ensuring that they do not inadvertently cause harm. Recognizing the state of a bird's feathers helps in providing proper care and management practices in falconry.