While you're here, how about contributing an item? - perhaps some news about something (success/failure/trouble), a bright idea you've had or that indispensible piece of equipment/software/website etc.
Based on my own research on NZ Falcon and involvement with falcons in NZ and overseas for many years, I can tell you that it is highly unlikely that they can be deterred. NZ Falcons are quite comfortable about hunting in close proximity to people, fear little and are easily approached. Consequently, they are unlikely to respond to deterrents. If they are taking free range chickens, it is because they are responding to fluctuations in their resource environment which is a natural ecological response. Options include;house the chooks (no longer free range), trap and relocate the falcons (although easy to trap, this is unlikely to solve the issue long term and arguable inappropriate given the status of falcons)keep chooks inside (i.e., manipulate their resource environment) for a while and hope falcons go awaya bit of advocacy and learning to live with it As for me, having falcons in my back yard would be a good reason to keep free range chickens - but I am biased.