So, the questions...
1) any tips on how to keep my grass thriving?
I can see that your yard is quite large. Your number of chickens does not look to be excessive. They will not destroy your yard at that rate. I suggest that you cut the grass slightly higher than average, and mulch, rather than bag. Fertilize, but don't use a weed killer pesticide. If in doubt, don't use granular fertilizer (slow release) , but opt for liquid applied like Miracle Grow Lawn Fertilized on a hose end.
2) any landscaping ideas for the rest of my chicken sanctuary? We get MAJOR rain and the chicken yard is in a low lying piece of our land. Especially near the fence which is especially prone to holding water.
3) HOW TO KEEP CHICKEN KILLERS OUT OF THIS AREA?! The fence that you see in the photo goes all the way around their chicken sanctuary.
You can create a large run area, rather than whole yard . You then can cover top with netting to protect from daytime attacks from hawks and other flying raptors. When you are outside with them, then you can open run and let them free range complete yard. Lock up the chickens in secure coop for the night. Raccoons and other nighttime predators can go over the fence you have. Reason for secure night time quarters. Most of your daytime predators, fence is good enough.
WISHING YOU BEST,,,,,,,,,,,,,,,,,,,,,,,,,, and
