Barn owl zoos
 

How do zoos and other such institutions normally obtain barn owls and barn owl eggs?

Sorry wrong section of the forum

Most of the native raptors I have seen on display are rescue/rehab animals that are unable to be returned to the wild. While I am sure there are several facilities where this isn't the case, it seems to be quite common.
The Federal laws surrounding raptors makes them very high profile and well protected, so I'd imagine it is extremely regulated, perhaps even more so than many of the other animals they maintain.