I have yet to see or hear a cuckoo Dave, I've never been lucky enough to see one. The migration of birds and animals always amazes me. There is a flock of Canada Geese who appear every year near the local reservoir.
We always got the first cuckoo (in Devon) on 21st or 22nd April without fail. Then we didn`t get them anymore. My Dad said that cuckoos always come back to breed in the place that they hatched and once that cycle was broken, then that was the end of that. I haven`t heard the cuckoo in our woods for at least 15 years.