Tarantulas

by Karen Miller, Master Gardener Entomology Specialist

This month, I decided to venture away from the insect topic and write about arachnids, most specifically the tarantula. Tarantulas are the largest and most revered of all spiders. They are part of the family of spiders called ‘Hairy Mygalomorphs’. Scientists believe the tarantula has been around for millions of years and has had little physical change over that time. There are from 700 to 900 species of tarantulas. The tarantula was formerly called banana spiders because tropical species arrived in cargos of fruit. Tarantulas are found in the rainforests and jungles of South and Central America, in Africa and in the southern part of North America. These large spiders vary in color and behavior according to their specific environments. Most tarantulas live in underground burrows. They use their fangs to dig the burrow themselves, or they can choose to just take over another animal’s burrow for their own. Like all spiders, tarantulas produce silk; however, they do not weave webs to catch prey. The females do weave silk to reinforce the inside walls of their earthen home. She will sometimes make a silk web door over the entrance hole. The male tarantula produces a silk mat to deposit his sperm on. The female will lay her eggs in the male’s sperm and seal both in a silken cocoon. She will guard the cocoon for six to nine weeks, at which time 500 to 1,000 tarantulas will hatch. Tarantulas have eight, closely grouped eyes; the large middle pair is rounded and has three eyes on each side. Each leg has two claws at the tip and a tuft of hair underneath. They have hairs on their abdomen that have sharp barbs on them. If threatened, the spider uses its hind legs to scrape the barbs from its abdomen and fling them in the directions of the threat. A nasty, irritating rash can occur if you are hit by the barb and the tarantula is left with a very noticeable bald spot on its belly. Tarantulas molt throughout their lives. Molting enables the spider to replace their exoskeleton as they grow. It also allows them to repair damage they may have sustained. For example: If a tarantula should lose a leg, a new one will appear, as if by magic, the next time it molts. Sometimes the regenerated leg will be shorter than the one that was lost, but over continuous molting, the leg will gradually get longer until it reaches normal size again. Male tarantulas do not live as long as the female and will not molt once they mature, which can be anywhere from two to five years. Females continue to molt and can live between 20-35 years in captivity. Tarantulas have few natural enemies. Some known enemies are the weasel, owl, hawk, skunk and some snakes, but the parasitic wasp is its most formidable enemy. This wasp will paralyze the tarantula with its sting and lay its eggs on the spider’s body. When the eggs hatch, the larvae feed on the still living spider. Bottom line…I know tarantulas give some people the creeps because of their large, hairy bodies and legs. Some people even have arachnophobia, a genuine fear of spiders, including the tarantula. This fear and/or creepiness are encouraged by movie directors who continue to feature tarantulas and other larger than life spiders in horror flicks. I believe this gives these cute, fuzzy spiders a bad rap. Fear not. These spiders are actually harmless. Although they can bite, the toxicity of a bite is about the same as a bee sting. The arachnid enthusiast in me says a tarantula would be an exotic pet worth having.

3-3-2016