I like the idea but how are you gonna make your nesting boxes. What is going to be the bottom that they lay in? Is this pen hurricane proof? ha I call my pen a Category 5! When you live close to the coast you have to keep that in mind. Have a nice evening!
I'm not quite envisioning how the pvc-hooped top is going to attach to the wall T-posts? Without making the whole thing twenty feet tall, that is. Or do you mean you're making a normal pvc hoop house (where the arcs of pvc go all the way down to ground level, anchored on posts sunk in the ground or at least on a 4x4 or 4x6 laid along the base of the wall) but are putting a t-post-and-wire-mesh fence *around* it?
Like the previous poster I'm also thinking you're going to need to give some thought to wind resistance -- it looks to me, from what I understand of the construction, like the sort of structure that just a moderate-strength thunderstorm could seriously disassemble. At the very least, your tarp will leave every time you have a storm, possibly taking bits of structure with it, because it will flap and because the wind can get under it so easily.
Nest boxes should not be a problem, though, youre just going to have them freestanding or built into the tractor portions, I expect?
I could never make any thing hurricane proof.. But hopefully if it over comes to that, I'll be able to provide them with something temporary but safe.. The nest boxes will be attached to the back of the tractors.. I don't have a picture for the tractors yet but I have it in my head..