Their hairy bodies and legs, eight eyes glittering in the moonlight make them fitting subjects of horror movies and tales in western literature, but actually they are reportedly quite shy and not especially aggressive unless cornered or otherwise threatened.
When upset they may slap their legs down on the ground or on their enemy. Hissing sometimes works for them too. But the most effective defense, short of fleeing was once observed in a patient of my optometrist brother. The young man complained his eyes hurt and were red and very itchy.
Upon examination, the eyes looked as if they'd been peppered with dozens of iron filings. It was my brother's first patient to have seriously upset a pet tarantula. Species in North and South America have special irritating hairs on their legs which can be flicked onto the skin or into the eyes of a threatening animal. In time the hairs would be absorbed and eventually disappear and apparently cause no permanent damage.
As a last resort, these spiders can inflict a venomous bite which they normally can use to capture crickets, scorpions, cockroaches, even young mice and birds. The bite to humans may be painful, but at least for our native species of tarantulas, there are no records of fatalities.
What is it about these big hairy spiders that causes our cultural collective shudder at these useful creatures? Bees also have venom but far fewer people have a bee-phobia. Is it having too many long hairy legs? Hunting at night? The eight eyes? Hiding out in our houses and woodpiles? Sucking the liquified life out of prey?
Aside from young people's Charlotte's Web, why haven't any authors yet managed to write a sympathetic and insightful novel for adults about the world of spiders? There's a fine example of this sort of writing, bordering on the sci-fi genre - Empire of the Ants by the French author, Bernard Weber. And come to think of it, why aren't children's books filled with talking animals ever labeled "science fiction" ?
Confessions of this writer - spiders are my challenge. Every time I make progress on appreciating these creatures there are setbacks. Even as I take a break from writing this to take a walk outside. I shake my hiking shoes out and a black widow drops to the floor, playing dead, but she isn't. All curled up into a tidy ball she suddenly flings out her spindly long legs, and voila! I dash for a jar to safely carry her away.
For more good info about keeping a pet tarantula - see http://atshq.org/articles/found.html