   Scorpions - April 23, 2003 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Of the thirty scorpion species found in Arizona, only one is life threatening: the bark scorpion (Centruriodes sculpturatus). In our area, the bark scorpion can be found in riparian areas and I have inadvertently brought them into my house with firewood. It is a climbing species that never burrows. This behavioral characteristic distinguishes it from other all other Arizona species. Other Arizona scorpions also sting and can cause serious health problems such as anaphylactic shock in sensitive individuals. Scorpions are the oldest known terrestrial arthropods (insects, spiders, centipedes, etc.) and probably were the first representatives of the group on land. Fossil scorpions, very similar to present-day species, are found in rocks over 400 million years old. Scorpions are extremely abundant in Arizona and one or more species can be found in virtually every habitat from mountaintops to desert floors. The devil scorpion (Vaejovis spinigerus) is common to the entire state. All scorpions spend the light hours under cover or in burrows. At night, they emerge within their individual defended territories and wait to ambush prey. Their diets consist of insects, spiders, centipedes, and occasionally small reptiles and young rodents. They capture their prey with their pincers and kill or paralyze it with a sting, which is thrust over the back. Scorpions are only active when nighttime low temperatures exceed about 77 degrees F. Scorpions have an elaborate courtship rituals which involves "dancing" back and forth. Mating is done after the male deposits a spermatophore (sperm package) on the ground, positions the female scorpion over the package, and she picks it up and fertilizes her eggs. Scorpion babies are live born and the female carries the young on her back until they have gone through their first molt. Then the young scatter to establish their own territories. They reach maturity in about one year and live for several years. Scorpions are food sources for several animals such as grasshopper mice, rodents, birds, and reptiles. Before you kill a scorpion, remember that scorpions are an important part of local ecosystems and should be appreciated by all-from a safe distance of course. They usually live outdoors, but can become a pest in some situations. For instance, if there is a cockroach infestation, scorpions may become more common because they have a ready food source. To protect yourself from an inadvertent scorpion sting, one should remove loose boards, woodpiles, rocks, and debris from areas immediately adjacent to the home. Wear leather gloves when moving object in yards and campsites. When camping, shake out sleeping bags, clothes, shoes, and other items that have been in contact with the ground. Always wear shoes when walking at night. Teach children to recognize and respect scorpions. Scorpions rarely enter houses. This occurs most frequently in newly developed areas (less than three years old) and is attributable to the disruption of habitat. Homes near rivers and arroyos can also experience an influx of scorpions during summer monsoons as they may have been washed downstream. To patrol for scorpions, you may want to purchase a portable black (UV) light. Scorpions fluoresce under a black light and can easily be located from a distance of several yards. Some people use the black light to locate them, pick them up with a pair of kitchen tongs, place them in a jar, and relocate them. Insecticides are ineffective and should not be used to control or prevent scorpions. The best management is to seal your home, clean up the area, and discourage insects and other prey. Respect scorpions and take appropriate precautions and you will minimize your chances of being stung. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |