in hunting applications, what is a call pen?

Answer 1

If you are in fact referring to a "Call Pen Trap", then I know what you are talking about.

A Call Pen Trap is used by Hunting Preserve Owners who release pen-raised Quail for Hunting and Dog Training purposes....These " Call Pen Traps" are a metal mesh trap used to re-capture/or recover Quail or other game birds that
survive after controlled release hunts are over, and the remaining birds are as a result still alive and free roaming..

Call Pen Traps are highly regulated and have to be registered and the number of traps allowed are based on the number of total acres a particular game reserve owns. Part of the legal registration requires that an actual "map" of the trap locations also be included as part of the registration process...These traps are common in the southern U.S.

Answer 2

don't think i have seen that.