Will my chooks escape?
Chooks are not nomadic. They stay reasonably close to their coop and generally don’t wander far. The need for fences is only if you think your neighbours would freak out if they found your chook in their garden. Some of my customers let their chooks free range in the front garden and even on the nature strip.
The risk is that a dog will come along and chase them far enough that they can’t find their way home, or will attack them. Many of my customers keep chooks successfully with an unfenced backyard, backing onto bush.