They have eight legs. They are large and hairy. They bite if you annoy them and they keep you awake at night. Yet some people consider tarantula spiders to be ideal pets.

When I went to see Fiona, Rosie, her pink toed tarantula was sitting in a glass case on the shelf behind her. “Is that thing real?” I asked. A stupid question, perhaps, as I’d come to talk to her about tarantulas but it looked like the kind of creation I used to make at infants school out of pipe cleaners and Plasticine.

“She’s asleep.” Fiona assured me. “She’s just had lunch.” Lunch, inside Rosie, was of course no longer visible. Supper to be, in the form of a large cricket was sitting at the other end of the tank.

Fiona explained, “Tarantulas won’t eat unless they’re fed with live bait. Supper must move. They sense the movement with the hairs on their feet. That’s how they know it’s there.”

How do you annoy a tarantula?

I examined Rosie more closely. She was the size of a saucer and very hairy. “Do you keep her because she’s furry,” I asked. “Is she nice to stroke?”

“You can’t stroke a tarantula,” says Fiona. “The hairs are urticating, that is, barbed and sharp – they can penetrate several layers of skin. Tarantulas can flick these hairs at you from their abdomens if you annoy them.”

“Which is the front end,” I asked.

“The end with the fangs,” Fiona replied impatiently.

Let me get this straight: you are keeping as a pet an outsized, fur-flicking arachnid, with fangs.

“Does she bite?” I asked. “Only if she thinks you’re food, or if you annoy her.” Fiona replied

How do you annoy a tarantula? It seemed like an important question.

“By mishandling her. But if she bites you, you must be careful not to drop her. Their abdomens are delicate and they can break open. That way, you lose your spider.”

So why does anyone keep tarantulas?

Late Night Rosie

“Tarantulas are endlessly fascinating,” says Fiona. “They are ideal pets for insomniacs because they truffle around at night - trotting round the tank and hunting. Rosie is a pink toed tarantula. She has pink toes,” she adds helpfully.

Can you have more than one? Or do they eat each other?

“Chilean Rose Tarantulas and Pink toed Tarantulas are quite docile and can live together in colonies. On the other hand, baboon spiders are vicious and you can’t keep them together. They rear up on their hind legs and hiss at you.”

And how do you get a tarantula as a pet?

“Keeping a tarantula is a serious commitment – they can live up to ten years,” explains Fiona. “Mine were rescued illegal imports. Illegal traffic in exotic species threatens the survival of these animals and it’s really important to make sure you get them from a reputable source. You must have a captive bred spider.”

And once you have sourced a breeder then what?

“Oh, they send them through the post,” Fiona replies.

I wonder if Postie knows what he’s carrying.

You can see tarantulas and other beasties at Edinburgh's Butterfly and Insect World