PREDATORY AND COMPETITIVE INTERACTIONS BETWEEN ADULT WOLF SPIDERS (ARANEAE: LYCOSIDAE) AND JUVENILE TERRESTRIAL SALAMANDERS (PLETHODON CINEREUS)

Abstract

Plethodon cinereus is an abundant salamander in forest floor ecosystems of eastern North America that has experienced recent population decreases caused by various factors. Although predators of higher trophic levels may cause significant mortality of urodele populations, it is currently unknown if large invertebrates such as wolf spiders (Araneae: Lycosidae) may also prey on salamanders. Because these generalist predators utilize the same resources as P. cinereus, a predatory relationship would be defined as intraguild predation (IGP), or the killing and eating of the salamander to reduce potential competition. The presence of an IGP relationship could have important implications on salamander species, as lycosids can reach high densities. To analyze the prevalence of predation, individuals of Rabidosa punctulata and Schizocosa avida were paired with P. cinereus in containers of three different sizes, the largest of which mimicked the home range of both organisms in situ. No observable interactions occurred between R. punctulata and P. cinereus, and their life histories were deemed temporally incompatible to constitute an IGP relationship. The life cycle of S. avida corresponds with the seasonality of P. cinereus, and predation of the salamander occurred when paired together in a small, simple container.