RELATIVE SEASONAL ABUNDANCE OF FIVE SPIDER SPECIES IN THE NEGEV DESERT: INTRAGUILD INTERACTIONS AND THEIR IMPLICATIONS

Abstract

ABSTRACT Current models indicate that intraguild predation is most likely to occur in communities with intermediate levels of productivity. Desert communities fit this criterion and also contain a disproportional amount of generalist predacious arthropods, in particular spiders, suggesting a high degree of intraguild predation in these communities. In this study we looked at intraguild predation in the Negev highlands among five species of spiders, two of which (Poecilochroa senilis, Gnaphosidae and Thyene imperialis, Salticidae) are predators of one or more of the other three (Latrodectus revivensis, Theridiidae; Stegodyphus lineatus, Eresidae; and Mogrus sp., Salticidae). However, unlike the simple interactions frequently modeled, we found complex interactions among the species which enhance coexistence. For example, evidence of higher-order interactions between Mogrus and Stegodyphus apparently enhanced the survival of Stegodyphus: during an annual cycle Mogrus, the preferred prey of Poecilochroa, was ...