Contributions to integrated management of synanthropic spiders

Arachnophobia, an irrational fear of spiders, is a prevalent anxiety disorder causing harmless synanthropic spiders to be viewed as pests that must be controlled. The objective of my thesis was to explore tactics other than pesticide applications for managing synanthropic spiders. Studying cues that affect settling decisions by cob-web spiders, I found that web architecture, rather than spider silk or silk-borne chemicals, affects settling decisions by females of the false black widow spider, Steatoda grossa. Investigating potential natural repellents for spiders in a multi-trophic context, I found that herbivore-induced plant volatiles are deterrent to S. grossa, but not to other spiders. As ants prey on spiders, I also explored the effects of ant chemical cues on avoidance responses of spiders. I found that chemical deposits of European fire ants, Myrmica rubra, deterred S. grossa, Western black widows, Latrodectus hesperus, hobo spiders, Eratigena agrestis, and – to some extent – cross spiders, Araneus diadematus.