The effect of predator chemical cue age on antipredator behavior in the wolf spider Pardosa milvina (Araneae: Lycosidae)

The wolf spider, Pardosa milvina, exhibits reduced movement when detecting chemical cues (silk and excreta) from a larger wolf spider, Hogna helluo. We tested if cue age influenced Pardosa activity. Pardosa response was measured during 1-h trials using video-tracking equipment. Five treatments of predator cues were used: 5-day-old, 1-day-old, 1-h-old, and fresh cues and a control lacking predator cues. Pardosa moved significantly more slowly on substrates with fresh or 1-h-old cues compared to all other treatments and spent less time walking in all Hogna treatments relative to the control except with 5-day-old cues. Pardosa survived longer in the presence of Hogna with fresh compared to older cues. Prey may evaluate cue age as a measure of predation risk and grade antipredator behavior accordingly.