I'm not doing anything special for Halloween, but I was amused by a local NPR news story that Halloween generally marks the end of the Tarantula mating season here in Arizona. That's right, Tarantulas have a mating season. Late summer to early fall:
Male tarantulas mature when they are 10 to 12 years of age, at which time they leave their burrows in search of females. Upon finding the burrow of a mature female—she’s usually at least 10 years old—the male will announce himself by stroking the silk at the top of the burrow and tapping particular sequences that the female responds to. During mating, the male must reach under the female to insert his pedipalp into her gonopore to deposit sperm. He is particularly vulnerable to predation by the female when mating. The male’s first pair of legs has a “spur”located behind the knee which he uses to hold the female above him during copulation. After copulation the male makes a hasty retreat. The female lays her eggs in a burrow, sometimes staying with them. The young remain in the burrow until they disperse.
They're a pretty common sight around here, but they might give some city folk a good Halloween scare.
I would have worn a costume if I could have found a "flying zombie vampire pig" disguise, but, alas, none were available.
Added: But this picture is pretty scary:
(found somewhere on the web)