So very sorry to hear you lost one of your babies. Soooooo sad!!!! A coon climbed up and over my 6 ft chain link fence and killed my main layer hen in the run. I learned right then and there, a top has to be on the whole run area for their protection. It killed the one hen and left the others alone. I thought that was weird as I figured if one got in it would kill all of them?????
I've read on BYC where people have run fishing line back and forth over a large run area, then hung aluminum pie pans and other things that blow in the wind so the hawks, etc. can see something on top of the run that they may run into. Don't know for sure if it works but it's sure worth a try.
Some BYC owners of chicks and/or ducks that use chain link kennels for coops/runs have said adding 1/2" hardware cloth, or chicken wire, on top of the chain link fence all the way around the bottom 3-4 feet of your kennel adds protection, as racoons can pull a chicken through chain link fencing enough to kill it.
I love my chicks and ducklings and am so glad to have them. It is definitely a great responsibility to keep them fed, watered, provide clean housing, a safe coop and run, etc. But I do it everyday because I love them and want them to grow into beautiful happy birds who hopefully will give us lots of eggs, besides being entertaining as well.
Remember when you build your coop to install air vents towards the top of the coop roof to vent hot air out in the summer, but just as important is to vent moisture up and out during the winter. A few vents would be great depending on the size of your coop. Good ventilation is very important...Moisture needs to vent...it comes from them breathing in the winter and from the moisture in their poop which can make them sick. A BYCer said during the winter vents in the top of the coop should be open regardless of how cold it gets....except for vents you may have placed low that would create drafts which aren't good for chickens in the winter.
I hope I haven't rattled on too much. These are just a few things I have picked up by reading BYC with all the wonderful helpful information for chicks and ducks, plus all the great ideas for coops/runs.
Good luck to you!
Me & dad with our two miniature daschunds, three Welsh Harlequin ducklings, two Rhode Island Red chicks, one Barred Rock chick, and one Buff Orphington chick.