Apparently, tarantulas are popular pets. The response to my Sept. 9 column seeking information about a tarantula that had stopped eating was substantial. My thanks to all the readers who wrote in reply. A condensation of the information that they offered follows.
A female tarantula stops eating for up to four weeks before she molts (sheds her skin) in preparation for new growth; that occurs about once a year. When a tarantula is molting, it often lies on its back and may appear to be dead. Within a period of 4 to 20 hours, a new body slowly emerges from the old shell. Females can live as long as 20 years. Males usually die in two to three years and molt once or not at all. As with some other species of spiders, the female may kill the male after mating.
The ideal temperature for the tarantula found in California is 75 to 80 degrees Fahrenheit. Tarantulas can survive at lower temperatures but tend to be less active. Some readers suggested putting four inches of soil in the spider's living quarters to retain heat; the use of a reptile hot-rock (available at pet stores) was also recommended.
As long as they have water, tarantulas can live for years without food. There is a report of one that lived for 16 years without eating. Usually, they only stop eating prior to molting, but some appear to go through a dormant period during which they do not eat for months. An owner should not be alarmed by such behavior unless the spider appears to be ill. Crickets are the main diet of pet tarantulas, although some readers use mealworms and hamburger for variety. The American tarantula rarely feeds on live baby mice, as I erroneously suggested in my prior column.