And they're clever. When they first hook themselves on and start the process of removing their meal, the unwitting carrier doesn't notice them. When the body does react it tells the fingers to start scratching, which is about the worst thing to do.
They're also quite selective about whom they bite. The Diary imagines that they view the passing human body in the same way as we eye up steak in the supermarket - there are better and worse cuts. The Diary doesn't suffer too much, but the Diary's wife is obviously a delicacy, as is one of its colleagues on HM Coastguard, who came back from a recent call-out with four new and very intimate friends.
There's plenty of advice on how to avoid them. They like hanging on bracken, where they're deposited by passing sheep and deer, but the better half collects them while picking raspberries in our back garden: we have no idea how the little wretches get there. Our cats carry round a menagerie of the blighters: being low-slung, they acquire them on their mousing expeditions.
Removing ticks isn't a problem - though it's best done sooner rather than later, as this Australian photo shows. We use the brutal approach, a pair of long fingernails or tweezers to pull them off, making very sure the whole of the head comes away, followed by a dab of antiseptic. We're aware that they can carry disease but the chances of contracting anything is so remote it doesn't bother us. For those that worry, there's plenty of advice here.
In general Ardnamurchan is wonderfully disease-free. We're off to Africa again shortly where disease is a big-time industry. Even nice people like Cheryl Cole get bitten there.