Who can explain the dead rabbits I keep seeing everywhere?

Can anyone explain why there are so many dead rabbits lying around at the moment? I’ve found three in my garden, untouched by predators, and the lanes nearby are festooned with carcasses. Also, my dog twice nearly caught a rabbit, which was behaving in a very un-rabbit-like lethargic manner. I wondered if, at first, it was myxomatosis, as the virus has adapted to a slightly less lethal form of late; hence the sluggishness. But the rabbits I found in my garden had none of those horrible tell-tale symptoms of myxy; the swollen eyes etc. Perhaps they are all committing suicide having been disillusioned by the comprehensive victory for the ‘No’ vote in the Scottish referendum. A chap I know locally reckons it’s a new disease, though, some ghastly brain tumour which results in them just dropping dead, on the spot. That would certainly fit with the dead rabbits I’ve found. Anyone know the answer? This is Fiver and Hazel and Bigwig we’re talking about, you callous buggers.