Rescued Besra
Hi,
I agree that the blood on the birds beak is most likely from prey that has recently been eaten.
We see alot of window strike cases and many of them cause mild or temporary concusion. Usually all is needed is to place the bird in a safe, dark & quiet environment such as a cardboard box for 30 minutes or so to allow it to recover, so you did exactly the right thing.
The fact that the bird became active and was able to fly from the box so quickly is a very good sign and from my experience the Besra will be fine.
Amanda
Raptor & Bird Rehabilitaion Section, KFBG
