The Influence of Sequential Male Courtship Behaviors on Courtship Success and Duration in a Terrestrial Salamander, Plethodon shermani



Sarah L. Eddy, Department of Biology, Hitchcock 430, Box 355320, University of Washington, Seattle, WA 98195, USA.



Most organisms use multiple cues across many modalities to assess potential mates. Salamanders in the genus Plethodon have an elaborate courtship display, yet previous studies primarily have concentrated on the influence of olfactory cues on courtship success. In this study, we tested whether two different cues (one chemical and one visual) affected courtship success and duration in the red-legged salamander, Plethodon shermani. By staging and observing over 180 courtship trials, we found that ‘foot-dancing’, a male visual cue performed in the earliest stages of courtship, significantly increased the likelihood that a male and female would progress to subsequent stages of courtship and, thus, the likelihood of insemination. In contrast, delivery of biologically relevant levels of a non-volatile pheromone (produced in a large gland on the male's chin) during courtship trials did not increase overall insemination rate success, but did significantly reduce the duration of one of the later stages of courtship, tail-straddling walk. Thus, we propose that early use of visual cues in Plethodon courtship, may (1) increase the detectability of the male message by increasing the range at which the male can be perceived by the female and (2) indicate the context of the male's approach and subsequent behaviors. In short, this study draws attention to the need to examine behavioral traits affecting courtship success at multiple stages and across several sensory modalities.