No single measure most deem practical for keeping poultry in a non-commercial setting is going to be predator proof long-term. Even the the heavier fencing and hot-wire can be defeated either because it goes into dis-repair or a predator simply puts more effort into task. Just give the predators time. When possible have more than one anti-predator system and have arranged in layers so predator can not come up with a method that works against all. A combination of fencing types, refuge for birds to go to, a dog, subdivisions within poultry yard to slow predator, care to avoid leaving excess feed or carcasses out, livetraps out for monitoring and simple monotoring by you can all be done. Also avoid having all birds in one containment unit so loss not as likely to be total. Sometimes we need to even step back and reconsider what breeds are suitable for situations where predators might be encountered.