Hi greenpeabean
So sorry to hear about the poor dead hog. That must have been a nasty shock for you.
Sadly, some hogs do die of natural causes. But, it isn’t always possible just by looking at them to tell whether they are healthy or not. Being wild animals they are likely to put on a good show of seeming well until they really can’t help it, by which time it can be too late.
Well done for reporting it to BTO you might also be interested in: https://www.hedgehogstreet.org/help-ive-found-a-dead-hedgehog/
Don’t forget to also register the hog on the Big Hedgehog Map (as well as the live ones). That way at least it’s death might be of help to other hogs in the future. I always think of it as a sort of memorial to the hog.
I hope the other hogs continue to be o.k.