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Behavioral repeatability greatly affects the capacity of an individual to respond to varying environments. When multiple behaviors within individuals are repeatable and correlated across time or across contexts, it is termed a behavioral syndrome. However, not all behaviors exhibit the same level of repeatability, and relatively few studies have examined repeatability in amphibians. We examined the repeatability of foraging behavior in the Eastern Red-backed salamander (Plethodon cinereus), a color-polymorphic terrestrial salamander, following a simulated predation attempt. We tested several hypotheses: (1) Simulated predation would negatively affect foraging, increasing latency to feed and decreasing the number of prey items eaten in a fixed time period compared to a control group; (2) Because striped color morphs of P. cinereus are more aggressive, striped individuals would exhibit "bold" behavior by resuming foraging sooner and consuming more prey; and (3) Foraging behavior would be more repeatable for males. We found that the predation treatment inhibited foraging behavior, although neither morphs nor sexes differed in either forging metric. The number of prey eaten was repeatable for all groups of salamanders. Latency to feed, however, was not repeatable for control salamanders. Simulated predation induced repeatable latencies, but when morphs and sexes were analyzed separately, only unstriped and male salamanders were repeatable, suggesting characteristics of these groups related to behavioral syndromes drive this response. We speculate that the greater repeatability of the unstriped morph's latency to feed may result from more frequent encounters with predators in the leaf litter matrix while foraging. Striped salamanders from the source population, in turn, exhibit greater territorial success, and thus may experience more variation in encounters with predators and conspecifics over the course of their lifespans. Our results illustrate the need to carefully define the behavior and subset of the population to be tested when studying behavioral repeatability or behavioral syndromes. [ABSTRACT FROM AUTHOR]

Several studies suggest that small terrestrial salamanders are important regulators of leaf litter arthropod communities, and likely contribute to ecosystem processes such as decomposition and nutrient cycling. Despite the recognition that salamanders have the potential to strongly affect ecosystem function through both direct and indirect pathways, little is known regarding the nature of interactions between small vertebrates and the large, predatory arthropods with which they share both microhabitat and prey. Our study was designed to explore interactions between Eastern Red-backed Salamanders, Plethodon cinereus, and spiders in the genus Wadotes in an eastern North American temperate forest ecosystem. We were particularly interested in teasing apart behaviors such as territoriality and intraguild predation in an attempt to determine specifically which interaction is most likely responsible for the observed negative relationship between salamander and spider abundance at our field site. Field data indicate that P. cinereus and large syntopic spiders exhibit negative spatial associations in the microhabitat beneath cover objects, a possible indication of interspecific territoriality. In our laboratory experiments, resident salamanders displayed agonistic postures similarly toward both intruding conspecifics and spiders, suggesting that salamanders may perceive large intruding spiders as competitors. Finally, we observed no injuries to individual P. cinereus or adult spiders even though occasional chases and bites by both were recorded during the behavioral trials. We found no evidence that adults or juveniles of P. cinereus were envenomated by adult Wadotes spp., and there were no instances of intraguild predation in this study. Multiple lines of evidence from this study, and others, suggest that the primary interaction between individuals of P. cinereus and large spiders is competitive in nature rather than predatory. We suggest that the cost associated with intraguild predation on salamanders with noxious skin secretions may preclude them from being preyed upon by spiders. [ABSTRACT FROM AUTHOR]