Birds have a relatively small supply of circulating blood in their bodies. If you notice any blood on the bird or on its cage or surrounding area, try to locate the cause of the bleeding immediately. Unchecked blood loss can result in death in a fairly short amount of time. Handle the bleeding bird carefully so as not to cause it to struggle and panic, which could result in more blood loss.
Once the location of the bleeding has been determined, try to stop the blood flow immediately. If the bird is bleeding from the beak (from flying into glass or another object), apply styptic powder or any cauterizing agent (cornstarch, flour, baking soda) by packing it heavily onto the bleeding area. Be very careful! If the bird is bleeding from a broken toenail, follow the same procedure as for the beak. If the bird is bleeding from a broken blood feather (a developing feather that still has a flowing blood supply in the shaft), pull the feather immediately with a pair of needle-nosed pliers. Grab the feather firmly at the base of the quill, and pull the feather in the growth direction. If the area continues to bleed after the feather has been pulled, apply a cauterizing agent to stop the blood flow. Keep a close eye on the area of injury even after the bleeding has stopped to ensure that the wound does not open again.