And if prey birds are lost so will all those birds of prey who kill and eat them when given half a chance. Foxes, hawks and other birds of prey will decline as well.
KY Jon - not sure I agree with this. Unless grouse moor management has changed since I studied it in the early 1970's (Master's degree at U. Aberdeen), gamekeepers kill every animal which could conceivably eat a grouse or an egg. They were the reason that peregrines, kites and eagles were exterminated in Scotland. Back then, a keeper's gibbet displayed everything from foxes through owls, ravens, stoats, weasels and even moles -an appalling slaughter of predators. Of course, killing raptors was not legal even then, but I heard of keepers being fired on the spot if a harrier (marsh hawk) was seen on a moor.
Can our UK friends tell us if such severe predator control is still the norm?