here in common places they just call them zip ties with no specification. I don't know if in some specialized shops there are uv rated, etc. mine probably are chinese. they (black) last 3-5 years.
lucky you! I have to dismantle pallets with twisted nails. it slows me down. at least I have got a few "motorbike" pallets that have good, new and good size wood. duck nesting boxes are my project for them.
my albanian neighbor (from my old place) taught me to use a smaller box with some pillow filling to keep chicks warm at night. works great. as I had a lamp accident (luckily woke up on time) I prefer to avoid to use lamp when I sleep. also I find chicks less stressed when sleep at night.
my grandparents had square wooden well above the ground and stone down. I wish I could find someone to make a well on my property. unfortunately people who know how to build it are too old to do the job and the young ones sit in the bars and play with their cell phones.