Thanks for all the help everyone! I do breed German Shepherds happyfrenchman, I do not keep them all in the same pen though because the studs will fight to the death if they get the chance. I have three studs and 3 large kennels, I keep one stud in each kennel and then the unrelated females that he breeds are kept in that kennel with him. Then the old, retired, dogs stay in the house. Each kennel has at least 3 dogs in it so hopefully that is enough to keep a big cat away.
Razzy101, the Blue Jay is a member of the corvid family, along with crows, magpies, and others, corvids will raid other bird's nests and eat the chicks and eggs. Corvids usually have pretty complex social structures and are very intelligent birds. Crows are much larger than Blue Jays and will kill young chickens and steel chicken eggs, I have not heard of Blue Jays doing this but I wouldn't be surprised if they ate an egg or killed a small chick, they should be no threat to an adult hen though, or even younger birds. Blue Jays can be annoying if you have songbird nests around that you like because they will hunt for the nests to eat what is inside, some of their favorite bird nests to raid are American Robins and open nesting finches and sparrows. They usually avoid dove nests, Oriole nests, cavity nesters, and swallows.
