Extension cord or solar powered will do. Former is cheaper on front end but cord may be headache during yard maintenance.
Poultry netting could also be used as suggested but cost much higher and it will likely be much larger / longer than actually needed. The electric fencing could be setup...
Birds will quickly learn to avoid fencing if you do not set it up so they can't access it. I would want fencing setup to provide an outside perimeter to deny predator opportunity to challenge coop / run construction. The smaller units are designed to keep a perimeter fence hot around several...
In this case you have a single known dog causing problem. Dogs ultimately of greater concern will be in future and likely not known to you until after they do their damage. For me, targeting a single dog works only if it is known. I have learned to use whatever methods work while I am not...