By posting this I am pretty sure I'm dooming another guinea to death. As soon as I think I am in a rhythm, something changes and they find another way to die. Over about 15 months I bought 11 adults, 10 teenagers, 8 keets and hatched 6 keets. Of the 35 I was steady at 11 for about a couple months, but went to 10 on Tuesday and will soon be 9 as a couple had problems laying their first eggs. The prior three died from a hawk, a neighbor's trespassing dog and exhaustion when one flew up into a tree before a blizzard and refused to come down for three days.
A lot of the early deaths were newbie error. My first 4 didn't sleep in the pen, at first, so I kept the door open. When they started to, they died. I learned raccoons can reach through chicken wire can decapitate keets (-5). I learned you can't keep the pen door
open with keets inside during the day in the spring because a mama fox will grab them and take them back to her den for her cubs (-3). I learned you can't keep the door
closed during the day in the winter, because there is not enough cover and there is no where to hide when the red-tailed hawk shows up (-4).
I keep tinkering with my system. When they all run off at once, they often come back one man short, so I try to keep them closer to the house. It helps if you keep 2-3 birds in the cage and let the others out. Currently I'm experimenting with a concept I call "idiot bird inertia." I have a 2x2' door at the top of the coop, at the end of one roost. I also built a one-way door at the floor of the pen. At any given time, there are a couple of birds that can't figure out how to get out or get back in, so I seem to always have a couple of birds in the pen, which keeps the others fairly
local, and I'm not fussing with who gets to be in and who gets to be out.
I think if I can keep them locked in the cage at night and fairly close to the house I am bound to lose about one per month from the occasional fox or hawk. I am trying to get to a point where I can stay above a certain critical mass where they can be sustained despite the 12-15/year loss rate. Hopefully my population is getting stronger and smarter. They are laying now and I actually have them laying in the pen. There are about 20 eggs in there and we'll see if/when one goes broody.
I have them because I want free range birds
and grass, and that has been a success. I also have them for ticks - we pulled 20+ ticks off of us last May and June, so the next 60 days will tell us if we have been successful in this endeavor.