Shilcusky, Aislinn, Ecology Program, Susquehanna University, 1858 Weber Way, 3498, Selinsgrove, PA, PA, 17870, shilcusky@susqu.edu; Ahmed, Faiza, Biomedical Sciences Program, Susquehanna University, 1858 Weber Way, 3498, Selinsgrove, PA, PA, 17870, ahmedf@susqu.edu; Persons, Matthew, J Ecology Program Susquehanna University 1858 Weber Way, 3498 Selinsgrove, PA PA,17870, persons@susqu.edu.
The semi-aquatic fishing spider, Dolomedes triton, deposits hydrophobic silk on the water as well as on emergent rocks and vegetation. Silk cues, although used primarily for intraspecific communication, have the potential to alert prey to their presence and mediate predator-prey interactions. We compared activity level, space use, and predation avoidance of two neuston-dwelling prey species: the water strider Aquarius conformis and the wolf spider Pardosa milvina in the presence or absence of Dolomedes and/or its associated silk. We measured Aquarius (n=152) and Pardosa (n=158) behaviors under four conditions: 1) containers with a live predator and its silk, 2) containers with silk cues only from Dolomedes, 3) containers with Dolomedes and no silk, and 4) control containers without Dolomedes or silk. We measured time on the water surface, emergent surfaces, and time climbing artificial vegetation across predator and silk treatments. We also measured time spent moving and attempted and successful predation among treatments containing a live Dolomedes. We found significantly lower activity for both Pardosa and Aquarius when live Dolomedes were present and both prey showed significantly stronger responses to female Dolomedes than males. Female Dolomedes were significantly more dangerous predators for Pardosa and Aquarius, killing more prey than males. Silk mediated few Aquarius behaviors, but predator silk did significantly induce climbing behavior and water avoidance in Pardosa. Dolomedes strike frequency toward Pardosa was significantly lower when silk was present and strike latency for Aquarius was significantly higher in the presence of predator silk. Our results indicate that both species show sex-specific predator avoidance behaviors and silk mediates some behavioral responses in both prey species but in different ways.
neustonic prey, hydrophobic silk, antipredator response, predation